Articles containing the keyword 'puu'

A process-oriented tree and stand growth model is extended to be applicable to the analysis of timber quality, and how it is influenced by silvicultural treatments. The tree-level model is based on the carbon balance and it incorporates the dynamics of five biomass variables as well as tree height, crown base, and breast height diameter. Allocation of carbon is based on the conservation of structural relationships, in particular, the pipe model. The pipe-model relationships are extended to the whorl level, but in order to avoid a 3-dimensional model of entire crown structure, the branch module is largely stochastic and aggregated. In model construction, a top-down hierarchy is used where at each step down, the upper level sets constraints for the lower level. Some advantages of this approach are model consistency and efficiency of calculations, but probably at the cost of reduced flexibility. The detailed structure related with the branching module is preliminary and will be improved when more data becomes available. Model parameters are identified for Scots pine (Pinus sylvestris L.) in Southern Finland, and example simulations are carried out to compare the development of quality characteristics in different stocking densities.

• Mäkelä, E-mail: am@mm.unknown
• Ikonen, E-mail: vi@mm.unknown
• Vanninen, E-mail: pv@mm.unknown

The writer reports in this discussion article of four stands in Finland that have died due to a bolt of lightning. A death of a group of trees because of lightning has been relatively uncommon for the forest professionals. The trees may not have no lightning marks. The four sites are presented in detail. Characteristic for this type of death of trees is, for instance, that trees have died within a circular area (of usually 30 m of diameter), only conifers have died, trees die from the top down, sometimes marks can be found in trees in the centre of the area, and under the bark may be brown patches or stripes.

• Nuorteva, E-mail: mn@mm.unknown

When Finland attained independence in 1917–1918, about 65% of her population made their linving from agriculture and only 17% from industry. Despite the fact that most sectors of the modern forest industry, i.e. sawmilling, pulp and paper making as well as plywood industry were then in existence a considerable proportion of timber was exported as roundwood.

It was reasonable to assume, however, that further economic development would reduce the roundwood exports to provide raw material for industry. The present paper investigates the Finnish roundwood exports in 1921–1986 largely from the point of view of this hypothesis. Examination of statistics is focused on the change of volume of exports in the major categories of wood, changes in the trade policies of consumer countries, changes in competition between exporting countries and changes in Finnish export policy.

The PDF includes an abstract in English.

• Holopainen, E-mail: vh@mm.unknown

Based on literature this paper describes the natural afforestation of Finland that took place after the last ice age and the changes which have taken place during the last 10,000 years. The origin and development of the vegetation and trees are related to the changes in the edaphic and climatic factors. The first tree species to arrive in Finland were the primary colonizing species, birch and Scots pine. The appearance of Norway spruce dates back to about 5000 B.P. There have been great changes in the species composition of Finnish forests during the last several thousands of years but some 2,000–3,000 years ago the various species reached their present balance. The epoch of naural forests, which had lasted some 9,500 years, came to a conclusion, however, when man started to have a marked effect on the forest’s development 300–400 years ago.

The PDF includes an abstract in English.

• Alho, E-mail: pa@mm.unknown

Ring width at breast height is presented as a function of stem radius at breast height, the ratio between the diameter of a tree and the basal area median diameter, site index, and density of stand. By means of a conversion model ring width at stump height can be estimated as a function of ring width at breast height.

According to previous studies substantially better wood quality can be expected if mean width near the pith at stump height decreases from 3 to 2 mm. According to the present study only on the poorest sites suitable for Scots pine (Pinus sylvestris L.) planting (poor Vaccinium type) the ring width is less than 3 mm at stump height even in the thickest trees. On more fertile sites a substantial increase in the recommended planting density is required, if the mean ring width is aimed to be less than 3 mm. On the best sites it is impossible to reach mean ring width of less than 2 mm, when the density is less than 4,000 stems/ha. Only the thinnest trees on the poorest sites can have a mean ring width less than 2mm.

The PDF includes an abstract in English.

• Varmola, E-mail: mv@mm.unknown

Properties of fibres in pulpwood, especially length, width and the thickness of walls in tracheids, are essential for strength properties of pulp and paper. Length and width of tracheids increase from pith to surface in radial direction. Young and small-sized stems have also smaller fibres. Small-sized Pinus sylvestris L. test trees had tracheids that were shorter both in stems and knot wood than those in normal sized trees. However, cell walls in test trees were as thick as in normal sized trees. It seems that especially the L/T -ratio (length/thickness) in small stems is worse than in normal sized pulp wood.

The PDF includes an abstract in English.

• Laurila, E-mail: rl@mm.unknown

The area of stands studied by line plot survey was 594 ha. On the basis of the length of the inventory line the estimated proportion of harvesting strips was 14% and that of ditch openings 6% of the area. The calculated strip road spacing was 29 m. The option of the minimum diameter made it difficult to use the number of stems as criterion for thinning intensity. Thinning intensity evaluated according to the basal area had been stronger than recommended with low values of dominant height and milder with high values. The estimated removal according to stumps was 38 m³/ha on the average between the strips. The real removal has, however, been larger than that, as the strip road openings are made in connection with the first thinning.

The PDF includes an abstract in English.

• Rantonen, E-mail: hr@mm.unknown
• Päivänen, E-mail: jp@mm.unknown

The study material consisted of 13 rather old Norway spruce (Picea abies (L.) H. Karst.) and 17 Scots pine (Pinus sylvestris L.) stands located in different parts of Finland. In each stand the seed crops, radial growth and amount of latewood were measured during a period of about ten years. Seed production reduces the radial growth of spruce and pine in the year of seed maturing. In Southern and Central Finland also the proportion of latewood is reduced. Seed production accounts for about 14% of the variation in radial growth of a spruce stand growing in Lapland, and 27% in other parts of Finland. In pine stands the seed crop explains 19% of the variation in radial growth in Lapland, and only 7% in the rest of Finland. In spruce stands an average seed crop reduces radial growth by 14% in Lapland and 5% in the rest of the country. An abundant seed production causes a reduction of about 20%. In southern parts of Finland, the proportion of latewood is reduced by 5% in an average seed year and by 24% in a good seed year. In pine stands an average seed crop decreases the width of annual ring by 5%, and a good seed crop by 15%. Outside Lapland, also the proportion of latewood is reduced: in an average seed year by 5%, and in a good seed year by 16%. The reduction in volume growth of spruce stands due to an average seed crop was estimated to be about 10% in Lapland, and 6% in other parts of Finland. A prolific seed production causes a reduction of 20%. In old pine stands the reduction is 5% in an average seed year, and 15% in a good seed year.

The PDF includes an abstract in English.

• Pukkala, E-mail: tp@mm.unknown

In laboratory studies the heartwood content seems to be the only natural property of a wood of different tree species influencing the decay resistance. Moistening and drying by diffusion happen quite slowly. Scots pine (Pinus sylvestris L.) sapwood takes moisture by capillary action quicker than pine heartwood and Norway spruce (Picea abies (L.) H. Karst.) wood. Swelling and shrinkage are also greatest in pine sapwood. Impregnation of pine sapwood can give it better hydrophobic and dimensional stability than that of pine heartwood.

The PDF includes an abstract in English.

• Kärenlampi, E-mail: pk@mm.unknown

The basic density of the wood of the rowan tree (Sorbus aucuparia L.) is almost the same along the stem but that of the bark is increasing along the stem. The moisture content of the wood and of the bark is increasing along the stem. Its strength in the bending and in the compression is high. The volume shrinkage is high.

The PDF includes an abstract in Finnish

• Maasalo, E-mail: km@mm.unknown

The purpose of the study was to determine the effects of the origin of seeds and the location of cultivation of Scots pine (Pinus sylvestris L.) on certain properties particularly important to the pulp industry. The research material consisted of six parallel trials of the same 12 provenances. Increment cores were taken of a total of 1,267 sample trees, 19 years old. The location of the trial site generally affected the properties to a larger extent than the origin of the seed. The effect of the variation of wood density and fibre yield on the cultivation values of the provenances was only a few percentages on average, however, at most the effect was nearly 10%. Eastern Finnish provenances adapted well to western Finnish conditions.

The PDF includes an abstract in Finnish and French.

• Velling, E-mail: pv@mm.unknown
• Nepveu, E-mail: gn@mm.unknown

A computer model was developed for predicting knottiness of wood material of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.) and birch (Betula sp). The prediction included location of knots, their size and quality, i.e. if they are dead or living knots. The model suits best for tree species where branches are born at the base of shoots, in Finland such tree species is Scots pine.

The usefulness of the model was tested in the prediction of knots in wooden elements of joinery industry. According to the results, the shape of cross section affects the surface quality of elements. Especially useful is a quadratic cross section as it increases the probability to get a knotless surface.

The PDF includes an abstract in English.

• Kärkkäinen, E-mail: mk@mm.unknown

A model was developed in order to describe the peeling of veneer for determining value relationship for birch veneer logs and stems. The model was based on selling prices of veneer and other products as well as processing costs. The model was utilized for determining the effect of various input variables on the log value.

According to the results, the effect of tree size was important for the value of raw material. Even knottiness had an effect although only in the higher manufacturing costs of knotty veneer were taken into account. Pruning was a method to increase substantially the proportion of knotless veneer.

The PDF includes an abstract in English.

• Kärkkäinen, E-mail: mk@mm.unknown

Variation of monoterpene composition of Pinus sylvestris L. was studied in Southern, Central and Northern Finland using data from both natural stands and plus trees. The natural stands were analysed using different techniques and for fewer terpenes than the plus trees.

There were large differences between areas in the proportion of 3-carene in trees from natural stands, as has been discussed by previous authors. The proportion of 3-carene is bimodally distributed and believed to be controlled by a single gene with large effect. For this reason, we stratified our samples into high carene (>10%) and low carene (<10%) groups. Univariate analysis did not reveal any additional differences between natural populations in different zones for components other than 3-carene. In plus trees, several components showed significant differences, but the proportion of 3-carene did not differ between areas. Multivariate discrimination analysis did not distinguish between areas for natural stands. However, for the plus trees discriminant analysis allowed us to discriminate between the zones relatively efficiently. The proportion of correct classification was greater than 64% using the best methods. The central zone was most distinct, and 80% of its trees were correctly classified. Broad generalizations are not possible due to the limitations imposed by our data. Our analysis of phenotypic variation does not support the suggestion that plus trees selected from the north represent a southern type.

The PDF includes an abstract in Finnish.

• Muona, E-mail: om@mm.unknown
• Hiltunen, E-mail: rh@mm.unknown
• Morén, E-mail: em@mm.unknown
• Shaw, E-mail: ds@mm.unknown

The aim of this literature review was to compare Finnish Norway spruce (Picea abies (L.) H. Karst.) sawn goods to Central European spruce sawn goods which contain fir in some amount. However, it was found that no statistically valid comparisons have been made. Therefore, conclusions have been based mainly on the relationship between various properties and growth rate. According to this analysis, most properties of Finnish spruce are better, although small in practice.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

Young Norway spruce (Picea abies (L.) H. Karst.) are susceptible to early summer frost damage. Birch (Betula pubescens Ehrh.) naturally colonize rich or fairly rich drained peatlands after clear cutting, and can provide protection for developing seedlings. The report describes the development of spruce stands after various types of handing of the birch nurse crops.

Different proportions of birch and spruces did not have any influence on the spruce stand production. In cases where the nurse crop stand is removed when the spruce stand age was 20 years and height 4 m the spruce suffered badly but recovered with time, reaching the spruce stand growing under a nurse stand within the next 20 years. The height growth of spruce depends on the density of the nurse stand, especially on fertile sites. The development of diameter growth also depends on the density of the nurse trees. Removal of the nurse stand in spruce stands on the sites concerned should be done when the spruce stand is 20 years old and at the height of 4 m.

The PDF includes a summary in English.

• Heikurainen, E-mail: lh@mm.unknown

Variation in tracheid morphology were examined for the bole wood of lodgepole pine (Pinus contorta Douglas ex Loudon) grown in Southern and Central Finland. Tracheid lengths were examined in a fast-grown and in slow-grown trees from three stands. Tracheid length increased with increasing height to 4–8 metres and decreased after that, and increased also with increasing age from the pith. The variation between stems was high. The shortest tracheids were about 1.11 mm near the piths and the longest about 4.10 mm near the bark.

Tracheid diameter and cell wall thickness were measured for the total number of 16 stems from Southern and Central Finland. Tracheid diameter increased with increasing distance from pith and the largest tracheids were at a height of 4–8 metres. Cell wall thickness varied independently of height in the stem. Summerwood cell wall thickness was twice that of springwood. There was a difference of 0.6 μm in springwood and 1.0 μm in summerwood double cell wall thickness between the two stands. Cell wall percentage was 29±4.7 in springwood and 69±7.3 in summerwood.

The PDF includes a summary in English.

• Saranpää, E-mail: ps@mm.unknown

Basic density and absorbed energy in impact bending were measured for 500 Norway spruce (Picea abies (L.) H. Karst.) samples from Northern and Southern Finland. Statistical analysis showed that the relationship between impact strength and basic density was significant and regression analysis showed that it was linear.

Furthermore, with constant density, the impact strength was higher in Northern than in Southern Finland. This was due to growth ring width: i.e. when density was kept constant the impact strength increased with decreasing growth ring width. In addition, when the growth ring width was kept constant, the basic density of wood was higher in Southern Finland than in Northern Finland.

The PDF includes a summary in English.

• Saranpää, E-mail: ps@mm.unknown

The study deals with the distribution of above-ground biomass of Vaccinium myrtillus L. along the vegetation continuum segregated by using phytosociological classification method composite clustering. The qualitative characteristics of forest sites corresponding to different vegetational clusters were defined on the basis of indirect gradient analysis of vegetation data and description of tree stand properties in stands in 160 sample areas in Southern Finland.

Six vegetation types differing from each other mainly in abundance of the most constant and dominant plant species were formed. Sample areas with rich grass-herb vegetation, as well as sample areas representing comparatively dry, barren site type were clearly separated from other groups of sample areas. Stand characteristics, particularly the proportional distribution of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) seems to be another important factor affecting the vegetation composition.

The lowest biomass values of blueberry were connected with herb-rich vegetation and shady spruce-dominated stands. Comparatively low values were connected to also other spruce-dominated sample areas. Pine-dominant or mixed pine-spruce stands the biomass values were significantly higher. Even if the site quality is essentially equal, the abundance relationships between Vaccinium myrtillus and other components of the ground vegetation may vary in wide ranges and cause difficulties in practical site classification.

The PDF includes a summary in English.

• Kuusipalo, E-mail: jk@mm.unknown

Empirical measurements showed that the strength of a dead branch of Scots pine (Pinus sylvestris L.) was related to the second power of the branch diameter and the third power of the basic density of branch wood. The same factors affected also the strength of living branches. Especially, the contribution of wood density was important. The significance of the results is discussed considering the natural process of self-pruning and its effect on the branchiness of the stem.

The PDF includes a summary in English.

• Kellomäki, E-mail: sk@mm.unknown

In order to evaluate the strength properties of boards made from small and large Norway spruce (Picea abies) butt logs, 15 small (top end diameter 13 cm) and 15 large (top end diameter 25 cm) logs were sampled from a sawmill in Finland. From each log two test pieces were made in order to measure the bending and compression strength, dry density and average ring width.

The boards from small logs were stronger and their density higher. When the differences between groups were analysed it was found that the strength was determined by the density and ring width. When the density was kept constant, the increase in ring width had a decreasing effect on the strength properties. Because there was a negative correlation between ring width and density, ring width alone had a great effect on the strength properties.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown
• Hakala, E-mail: hh@mm.unknown

A population consisting of 450 Norway spruce (Picea abies (L.) H. Karst.) samples was gathered from northern and southern Finnish wood. The static bending strength was affected greatly by the density of the wood. However, keeping the density constant, the bending strength was higher in northern than in southern Finnish wood. The reason was the effect of the growth ring width.

The basic density was affected by the growth rate. Keeping the growth ring width constant, the basic density was over 5 kg/m³ lower in northern than in southern Finnish wood. This result supports the earlier findings on the effect of latitude.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown
• Dumell, E-mail: od@mm.unknown

Using literature and a simulator experiment, an ordinary processor and a grapple loader processor were compared in conditions corresponding to thinning later than the first commercial thinning. Visual bucking only was employed in the simulator experiment. The strip road spacing was 30 m and there was no preliminary skidding of the trees. The simulator experiment confirmed the view reached in the literature that work productivity of the grappler loader processor is 20–40 % greater than that of an ordinary processor provided that the stem size is under 0.2–0.4 m3.

The PDF includes a summary in English.

• Harstela, E-mail: ph@mm.unknown
• Maukkonen, E-mail: am@mm.unknown

A material consisting of 21 common alder (Alnus glutinosa (L.) Gaertn.) trees from 11 stands was collected. From each stem discs were sawn by 2 m interval. Samples were taken of the discs from various distances from pith. They were macerated and the average fibre length was based on 50 observations.

The fibre length increased significantly from the pith to the disc surface. The increase was approximately similar at various heights of the tree. The tree characteristics had only minor effect. However, near the pith the increase in fibre length was higher in trees with wide growth rings than in other trees. Near the disc surface the growth rate had no effect. In typical pulpwood bolts the average length was 800–950 μm which corresponds well to the data given in the literature.

The PDF includes a summary in English.

• Haarlaa, E-mail: rh@mm.unknown
• Kärkkäinen, E-mail: mk@mm.unknown

Light and economic FM-CW radar has been developed for controlling the bearing capacity of ice roads and landings on ice used for timber transportation and storage of timber in Finland. It was tested on natural ice and ice roads of three lakes in Southern Finland and one location on sea on the southren coast of Finland (a total of 166 observations). Ice thickness varied from 0 to 100 cm. Correlation coefficient between auger and radar measured ice thickness was r=0.99 and absolute error varied from -10 to +7 cm. The quality of ice had no influence, but by improving the interpretation of results, also the quality factors might be detected.

The PDF includes a summary in Finnish.

• Saarilahti, E-mail: ms@mm.unknown

The objective of the investigation was to determine the differences between timber grown on a peatland before and after draining, in respect of compressive strength parallel to the grain, static bending strength and density. In addition, the characteristics of boundary zone between the wood formed before, and after the draining with wider growth rings was studied. 41 Scots pine (Pinus sylvestris L.) and 22 Norway spruce (Picea abies (L.) H. Karst.) trees were studied.

The compressive strength of pine usually decreased from the butt end upwards, but no trend was observed in spruce wood. In coniferous trees, wide-ringed wood formed subsequent to draining was slightly lighter than the close-ringed wood produced prior the draining. The density of pine as well as spruce increases as the width of the growth rings decrease up to a certain limit. The strength of the different kinds of wood seems to decrease from the butt end upwards.

In both species, the compressive strength parallel to the grain and the bending strength are lowest in such wood that contains exclusively wide-ringed wood formed subsequent to draining. Also, compressive and bending strength increase with decreasing width of the growth rings. The longitudinal shrinkage of compression wood in spruce was several times that of normal wood, and the bending strength was lower than that of normal wood particularly in spruce. The compressive strength parallel to the grain in dry condition was, however, higher than in normal wood both in pine and spruce.

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• Ollinmaa, E-mail: po@mm.unknown

Questionnaires were sent out to determine the volume of wood harvested from peatlands during 1978 and the harvesting problems encountered. In total there were 110 responses which accounted for 8 million m3 of wood harvested, of which 1.0 million m3 (14%) was harvested from peatlands. The largest proportion of wood harvested from peatlands was during the winter. Most of the respondents reportet that they wait for the soil frost to set before harvesting is started on peatlands. Respondents indicated a total of 263 machines bogging down in to the soil or, for 1978, a total for Finland of 750 to 1,000 machines.
The PDF includes a summary in English.

The PDF includes a summary in English.

• Saarilahti, E-mail: ms@mm.unknown

The aim of this study was to establish from the literature the purposes and for which aspen (Populus tremula L.) and related poplar species are used and can be used.  According to the literature, numerous Populus species can be utilized in the industry with success instead of light softwood species in addition to them. The main emphasis is in the growing of large-sized timber, and there is no clear trend to changing to the short-rotation forestry of poplar. However, the utilization of the good sprouting properties of Populus species will probably increase as this regeneration method is cheap.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

The aim of the study was to find out the effect of the working place meetings on the increased cooperation between workers and supervisors, the improved work performance, the intensified use of machines and the improved job satisfaction. In the study loggers, forest machine operators and forement were interviewed. The results showed that the working place meeting is a useful means to realise the above-mentioned aims.

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• Kyttälä, E-mail: tk@mm.unknown

On the basis of a limited material, the drying of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) timber at room temperature decreased the thickness of the bark proportionally to the decrease in the moisture content. The decrease was the greatest in the middle portion of the trunk. In the spruce material, the decrease in bark thickness was exceeded by the shrinkage of the wood. During soaking, the bark thickness of both tree species decreased, too, contrary to the presupposed hypothesis. In both cases, the shrinkage was the greatest in the middle portion of the trunk. In the spruce material, the decrease in bark thickness was exceeded by the shrinkage of the wood. Possible explanation for the phenomenon is discussed.

The PDF includes a summary in English.

• Kellomäki, E-mail: sk@mm.unknown

A material of 478 birch logs were measured. The horizontal diameter was on average larger than the vertical one, the difference increasing with the increasing diameter. The reason was supposed to be the effect of sweep and out-of-roundness of logs. The difference between the actual and nominal length increased with the increasing lengths, but decreased with increasing diameter.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

In the first part of the study the hindrance of the remaining trees when felling trees by machines working from the strip road in selective thinning was studied on the basis of the literature. In the second part there was geometrically studied the need of schematic thinning in some type stands when bundles are pre-skidded straight-lined to the strip road. In average only 0-1 trees per pre-skidding trail needs to be removed. It was concluded that trees removed from the pre-skidding trail do not significantly increase the need of schematic thinning. Remaining trees do not limit the length of machine booms if the pre-skidding trails are planned during the felling.

The PDF includes a summary in English.

• Harstela, E-mail: ph@mm.unknown

Material for this study was collected from 26 stands marked for clear cutting in Southern Finland. The volume of decayed Norway spruce (Picea abies (L.) H. Karst.) timber and pulpwood was determined by deducting the volumes of these assortments (as recorded on the measurement certificate) from the volume of the standing trees. To obtain the economic loss, the volume of decayed wood was multiplied by the difference in stumpage prices between spruce timber of pulpwood and pine pulpwood. In the 17 stands of Buyer A the loss in timber volume caused by decay was 5.84% and the loss in stumpage price 2.84 Fmk/m³ (means weighted by volume). The corresponding figures in the 9 stands of Buyer B were 10.87% and 5.50 Fmk/m^3, respectively.

At the mean stumpage price level for the felling season 1977-78 the losses in the stands m.f.c. mentioned above were 2.87% per unit price in the stands of Buyer A and 5.75% in the stands of Buyer B.

The PDF includes a summary in English.

• Tuimala, E-mail: at@mm.unknown

In this study the loose volume of 58 piles of pulpwood were measured before and after barking by rotary ring barker. The volume was 2,121 m³. A recommendation is made, based on the results of the study, concerning the barking loss from piled wood: for green Scots pine (Pinus sylvestris L.) pulpwood, 8.8% of the stacked volume; for seasoned pine pulpwood, 6.1% of the stacked volume; and 8.0% for birch (Betula sp.) pulpwood, green and seasoned. The amount of bark left on bolts was small for pine bolts, namely 0.33%, but quite large for birch bolts, 2.84% of the green weight.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

The paper deals with the problems of the preservation of the redwood groves (Sequioia sempervirens (D. Don) Endl. and Sequoiadendron giganteum (Lindl.) J. Buchholz) in California. The activity to protect these groves from flood and fire may finally lead to dying of these long-lived trees. A program to use prescribed burning as a tool for the management of natural ecosystem has been started.

The PDF includes a summary in English.

• Nuorteva, E-mail: mn@mm.unknown

The aim of the present study was to register the curly birch (Betula pendula f. carelica Sok.) plantations established in Lapland and to determine their location and present condition. The information was obtained by means of interviews and visual observations.

In Lapland, the growing of curly birch started in 1950’s and the early 1960’s. During this period, in the different supervisory areas of Lapland, the National Board of Forestry established curly birch stands totalling approximately 30 ha, including about 34,000 seedlings. The bulk of the plantations have been destroyed by animals. On the other hand, the curly birch experimental stands established by the Finnish Forest Research Institute have thrived. The private sector of Forest Management has been engaged in the production of seedlings on a large scale and, as a result of this, curly birch trees are frequently seen as ornamentals in Rovaniemi and in other localities in Lapland. When taken care of, curly birch thrives in Lapland and produces I-class curly wood.

The PDF includes a summary in English.

• Etholén, E-mail: ke@mm.unknown

The effect of nitrogen fertilizers on the photosynthetic capacity of conifers is assessed on the basis of literature. The review emphasizes the role of changes of needle mass as a factor affecting the result of nutrient application. In particular, the increase in needle mass results in a considerable increase in photosynthetic capacity. The effect of fertilization on the photosynthetic rate seems to be of minor importance. The effect on the photosynthetic rate is, however, poorly documented as is the case for the effect of fertilization on the respiration rate. There is evidence that proper application of nitrogen fertilizers may double the photosynthetic capacity of conifers, mainly as a result of increase in needle mass.

The PDF includes a summary in English.

• Kellomäki, E-mail: sk@mm.unknown

According to the available literature, the times when pulpwood limbing was made by axe and barking by hand tools, barking either had no effect on the pile density (if limbing quality was good) or increased pile density (if limbing was bad). When rotary barking machines are used, the branch stumps remain intact during barking. Therefore, if there are branch stumps in the pulpwood, barking decreases the pile density. Nowadays, when power saw limbing is a common practice in Finland, barking presumably greatly decreases the pile density, due to the fact that in power saw limbing branch stumps are numerous and high. Therefore, the method to estimate the solid volume of a pile of unbarked pulpwood are not applicable to barked pulpwood without modification.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

The distribution of the dry matter and nutrients in Scots pine (Pinus sylvestris L.) tree stock growing on a Vaccinium type site, ground vegetation, and humus were determined in the study. The greatest part of the dry matter in the tree was found in the stemwood. The living branches, roots, bark, needles and dead branches decreasing order of magnitude made up the rest of the biomass. The trees contained over 90%, the field layer vegetation 3% and the bottom layer vegetation 2% of the dry matter in the tree stand. The tree stock contained 86–95% of the total amount nutrients in the stand. The field layer vegetation contained less nutrients than the bottom layer vegetation. Nitrogen, however, was an exception, the amount being approximately the same in both vegetation layers. 

The PDF includes a summary in English.

• Lehtonen, E-mail: il@mm.unknown

In this study two methods of determining the basic density of total tree chips are compared. The method of Mäkelä (1977) is based on the volumes of Scots pine, Norway spruce, birch, and alder in a logging area, and the age of the trees. In the other method the basic density of total tree chips is measured by the common displacement method. The correlation was 0,730 in the material of 22 logging areas. Besides this it was found that the basic density of chips increases as the size of the chip particles increases with the exception of the smallest particles.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

In this paper the system of collective timber price agreement in Norway is described. The history of »collective behaviour» in the roundwood market can be tracked far back in history, with different degrees of importance, and it has totally dominated the price-formation of roundwood from the 1950’s until the present. In trying to answer the question »What has been the effect of the collective price agreements» a few theoretical market models are used and the empirical data are also employed. Both the theoretical discussion and the empirical data seem to indicate that the forest owners are better off with collective price agreements than with a situation where there are no organized price-negotiations.

The PDF includes a summary in English.

• Høsteland, E-mail: jh@mm.unknown

The amounts of harvestable logging residues and stump and root wood were examined in the area where 100,000 solid m³ of stemwood was cut in 1975. The cutting amounts of stemwood from work sites suitable for harvesting of logging residues was 35,000 m³, and suitable for harvesting of stump and root wood 38,000 m³. The increase in the yield of wood (without bark) from logging residues compared with the unbarked stemwood was 2.4%. The same percentage of wood from stump and root wood was 5.0–5.8% depending on the harvesting loss.

The PDF includes a summary in Finnish.

• Mäkelä, E-mail: mm@mm.unknown

A method is presented in this study for calculating the basic density of whole tree- and logging residue chips and the results of trial measurements on some commonly used chip sorts. The basic density of Scots pine whole tree chips was found to be 1–18 kg/m³ smaller than that of pine pulpwood of the same age. The basic density of Norway spruce whole tree chips was 4–22 kg/m³ greater than that of similar aged pulpwood. The basic density of birch whole tree chips was 4–16 kg/m³ and grey alder whole tree chips 7–24 kg/m³ greater than pulpwood of the same age. The basic density of conifer logging residue chips was considerably greater than that of pine and spruce whole tree ships.

The PDF includes a summary in English.

• Mäkelä, E-mail: mm@mm.unknown

According to the literature, the mechanical strength of the green reaction wood of softwood species (compression wood) is greater than that of normal wood. Drying increases the mechanical strength but less in reaction wood than in normal wood. In particular, the tensile strength along the grain and the impact strength are lower than in normal wood. The compression strength and possibly bending strength are greater, however.

The properties of the reaction wood of hardwood species (tension wood) differ from those of softwoods. When green, all mechanical properties are weaker than those of normal wood. When dried, the tensile strength and impact strength are better and compression strength lower. There is no great difference in the bending strength.

When the higher density of reaction wood is not taken into account and there are no impact forces, the mechanical strength of reaction wood in sawn goods etc. does not differ so much from that of normal wood. The harmful effect of knots, for example, can in practice be much greater.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown
• Raivonen, E-mail: mr@mm.unknown

According to the available literature, the appearance of Parana pine (Araucaria angustifolia (Bertol.) Kuntze) wood resembles that of Scots pine (Pinus sylvestris L.). The anatomy is quite different, however. There are no resin canals and fusiform rays with resin canals in Parana pine. They are abundant in Scots pine, however. The basic density of Parana pine is higher. In both species the density increases from the pith outwards, the maximum being reached at the age of 100 years. Compression wood is more common in Parana pine than in Scots pine, and this makes the longitudinal shrinkage of Parana pine greater than that of Scots pine. Otherwise the shrinkage properties do not differ. The mechanical strength is of the same magnitude with the exception of hardness, where Parana pine is superior.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

This study was carried out on behalf of the Central Association of Finnish Forest Industries (now Finnish Forest Industries Federation) in order to obtain information about the wood raw material situation, to serve, in turn, as a basis for the forest industries’ long-term planning. The study deals with the potential supply of roundwood, industrial residue and forest residue by the year 200 by five wood-supply areas. Examination of the situation during the period of 1972–80 is based on available balances and that concerning the period 1985–2000 in the estimated quantities available for industrial use.

The PDF includes a summary in English.

• Suomen Metsäteollisuuden Keskusliitto, E-mail: –

In this study the area, 8 diameters, and 16 radii were measured of 174 discs representing aspen logs in a mill. The average difference between the largest and smallest diameter was 18 mm, or 7% of the longest diameter. The difference between the largest and smallest radius was 29 mm, or 22% of the longest radius. The diameter was on the average 2.4 mm longer than the two corresponding radii.

The exact area of each disc was measured using a planimeter. In comparison, the area based on the circle formula the diameter being the arithmetic mean of largest and smallest diameters overestimated the area by 1.7%. The results also indicated that the use of random direction in the measurement of diameter overestimated the cross-sectional area on the average by 1.8%.

The study is continuation of the earlier study where the bibliography is presented. As far as the results are comparable, they support each other.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

In the study the proportion of branch samples of various diameter were studied. The branches were taken from small trees to be harvested by total tree chipping method. The material consisted of 1,056 branch samples of birch (Betula verrucosa, now B. pendula Roth, and Betula pubescens Erhr.), Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) at intervals of 20 cm along each branch.

With exception of the basic density of bark, there was a relation between all the other properties which were studied and the diameter. Even when the effect of diameter was eliminated, in many cases the effect of the distance of the samples from the stem became apparent.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

In this study the width and height of 1,588 uniseriate and 454 fusiform rays were measured from tangential sections of four Scots pine (Pinus sylvestris L.) trunks. The samples represented various height levels and distances from the pith. The average width of the uniseriate rays was 19.7 μm and that of the fusiform rays, 51.9 μm. The average height of the uniseriate rays was 215.7 μm and that of the fusiform rays 406.2 μm. Due to this difference in height, it may be possible to develop an automatic system for distinguishing between uniseriate end fusiform rays on the basis of their height.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

The article reviews the position of the Department of Forest Technology in Finnish Forest Research Institute, among Finnish establishments in research on forest work. In addition, it describes the current research programmes of the departments both in wood harvesting studies and studies on silvicultural work. The equitable aims of the former are to increase productivity, lower the cost level, ease the work and improve job satisfaction, as well as to improve the utilization of wood raw material. The latter aims at e.g. improvement of the biological results.

Future prospects are surveyed from the point of view of the goals imposed by the State on the research and, on other hand, the appropriations earmarked for forest work science. A regrettable conflict has arisen between them.

The PDF includes a summary in English.

• Hakkila, E-mail: ph@mm.unknown

The utilization of stump and root wood is analysed in this paper on the basis of literature from middle of 19th century to the present date. According to the information available, the utilization of pine stumps in tar production was small compared to that of peeled Scots pine stemwood in the 19th century. During the 1st and 2nd World War the utilization of stumps for tar production reached its highest levels. Other industrial utilization of stumps has been small up to the present time but now stumps are beginning to be used in the pulp industry.

The greatest amounts of stumps have been utilized by the rural population. Stumps were used as fuel. In the thirties, the yearly amount used was over 200,000 m³ (solid measure), and even in the sixties over 100,00 m³. No industrial utilization method has yet reached these levels.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

The material of this study consists of 1,080 Scots pine (Pinus sylvestris L.) saw logs measures in two saw mills in Northern Finland. The largest and the smallest top-diameter of each log was measured under bark. According to the results, the ovalness was rather small, 1 mm or 4.9% on average. On the other hand, only 14.3% of all logs showed a diameter difference smaller than 2%. The ovalness was larger than 10% in 5.8% of all logs.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

The ash content has been found to correlate with the fertility of peatlands. Relationship between height of 80-year-old stands and ash content of peat in topmost 30 cm layer was examined in Lithuanian conditions. On drained peatlands with ash content of peat from 3% to 8% pine stands increase in height. Ash content of peat being about 7% Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) stands on drained sites are found to be of equal height. Ash content of peat more than 8–9% has no significant effect on growth of pine or spruce stands. Birch (Betula verrucosa (B. Pendula Roth.) and Betula pubescens Erhrh.), stands are less sensitive to ash content of peat compared with other species. Black alder (Alnus glutinosa L. Gaertn.) stands occurred in sites with ash content of peat more than 8–10%. The height of the stands become equal both in drained and undrained sites in the cases where ash content of peat is about 16–18%. Ash (Fraxinus exelsior L.) stands attain high productivity on drained sites with ash content of peat about 20%.

The PDF includes a summary in English.

• Kapustinskaité, E-mail: tk@mm.unknown

The aim of the study was to determine the extent to which the cross section of birch (Betula sp.) and aspen (Populus tremula L.) logs differ from a circle and to test some simple methods for measuring the cross-sectional area which can be used, for instance, for determining the volume of the logs. The material consisted of 420 debarked birch disks and 240 aspen disks which were representative of the logs arriving at two factories.

The convex deficit values for the material were very small, the cross-sectional area error being in general less than 1%. On the other hand, the other parameters deviated from the circular form to quite a large degree. It was also evident that the radii measured from the piths to the surface of the wood varied considerably more in the same disk, as regards length, than the diameters measured in different directions.

It was evident that the shape of the average cross-sectional area was not in general elliptical. It thus appears that any method for measuring the cross-sectional area which is based on elliptical formula is not suitable. The method which gave the best result was that in which the cross-sectional area was taken as the average of the area of the circle calculated from the smallest diameter and that calculated from the diameter passing at right angles to it. This method also appeared to be the best for disks which deviated to quite a large degree from the circular form. The suitability of this method is increased by the fact that the relative error is only slightly dependent on the size of the disk.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

During the next decade there will be a marked increase in the allowable cut in drained peatlands. At the same time, the mechanization in logging proceeds, and in short-distance haulage the use of forwarders will increase. This study, based on literature and some observations, deals with logging conditions in drained peatlands with special reference to the suitability of heavy logging machines for use in such terrain. In addition, soil frost and the bearing capacity of the frozen peat soil were studied.

Freezing of the soil in a drained peatland area depends prevailingly on the weather conditions during early winter. The factors influencing soil freezing of a drained peatland are completely different from those regulating the freezing of natural peat soils. The frost penetrates in general deeper in the drained than virgin peatland. The topmost peat layer does not, however, freeze uniformly. Generally speaking, the bearing capacity of a drained peat soil is lower than that of undrained peat due to lower water content.

It is concluded that heavy logging machines are probably not fitted for use in drained areas on peatland even if the average soil frost values recorded would suggest it. Moreover, because of their extremely superficial root systems, peatland forests are exposed to damages by heavy machines in thinning operations.

The PDF includes a summary in English.

• Hannelius, E-mail: sh@mm.unknown

Peat industry is rapidly expanding in Finland. Consequently, during next decades peat will be removed from thousands of hectares. Because timber production probably is the most rational use of this area after the peat production has ended, some experiments of afforestation of such areas have already been conducted. This article reports results of two experiments which were started in Kihniö, Western Finland, in 1953 and 1964.

In the first experiment fertilization with wood ash proved very effective whereas seeding and planting without fertilization resulted in almost complete failure. In the second experiment, interplanting with grey alder (Alnus glutinosa L. Gaertn.) greatly promoted the growth of Scots pine (Pinus sylvestris L.). The effect of slight fertilization lasted a few years only. The reasons for the remarkable effect of alder need further research. Although alder is known as a nitrogen-fixing plant, its beneficial effect was most clearly seen in the K and P contents of pine needles. Inoculation with mycorrhizal fungi was beneficial but not necessary. Experiments hitherto show that afforestation of bogs after peat removal is possible although some additional measures like fertilization or interplanting with alder may be needed.

The PDF includes a summary in English.

• Mikola, E-mail: pm@mm.unknown

The planning of timber production in a forestry unit is divisible into two phases. In the first phase, planning provides the decision-maker with a number of possible timber production policies; these policies define the production possibility boundary. After the decision-maker has chosen one of these policies, planning moves to the second phase, in which a detailed programme is prepared with a view to meeting the requirements of the timber production policy accepted. The paper indicates one possibility of solving these two tasks simultaneously. In the first phase, the solution of the primal linear programming problem is employed and in the second phase the respective dual or shadow price solution.

The PDF includes a summary in English.

• Kilkki, E-mail: pk@mm.unknown
• Pökälä, E-mail: rp@mm.unknown
• Siitonen, E-mail: ms@mm.unknown

The paper deals with the optimization of roundwood transport in cases where many destinations for it exist and where several means of transport are available. It is also understood that the capacities of the factories to which wood is transported can be used at varying degree. A model was developed for a case such as Finland which sells most of its products abroad.

In the above case, the optimization of roundwood transport does not necessarily mean minimization of transport costs. What is aimed at is to obtain, by using different combinations (mill destinations and the media of transport) the maximum difference between the allowable cut (calculated) and real (actual) transport costs.

The PDF includes a summary in English.

• Roitto, E-mail: yr@mm.unknown

The aim of the present study was to collect information presented in literature concerning the development and germination of the seeds of coniferous trees with special reference to those species which thrive in the conditions prevailing in Finland. Along with the increase in the importance of direct seeding as a silvicultural means in Northern Finland, there is a growing demand for methods by means of which the germination of seeds could be promoted. According to the results obtained from previous studies, such a method can be found, provided that a practically usable and reliable pre-germination method is developed.

The PDF includes a summary in English.

• Lähde, E-mail: el@mm.unknown
• Pahkala, E-mail: kp@mm.unknown

The study deals with economic significance of forest landscape planning models used in regional planning in Finland. The »judge»-method is used among professional foresters working on private forestry boards in Southern Finland to define their view of what would be moderate level of costs of landscape management for private forest owners. A sample of 154 forest professionals working in district forestry boards in Southern Finland was sent a sociological questionnaire.

It was possible to form three hierarchical moderation classes by statistical grouping of judgement distributions. Prolongations in rotation ages and restrictions concerning ditching of forested bogs, forest read building and clear-cutting were considered the most immoderate models. Rather or wholly insignificant were evaluated such management models, which mean restrictions in »old fashioned» methods or which are already used in practice.

The PDF includes a summary in English.

• Lovén, E-mail: ll@mm.unknown

In this study a formula has been developed to describe the influence of the change of cost level on such a mechanization prognosis, where is assumed that wages and machine costs bear compound interest. In the study there are some numerical examples.

In the formula p1 = annual per cent increase of wages, p3 = annual per cent increase of machine costs, p2 = sudden and incident per cent increase of machine costs, and tv = delay in the profitability of mechanization.

The PDF includes a summary in English.

• Harstela, E-mail: ph@mm.unknown

In this paper the use of butt and top diameters of pulpwood bolts for volume determination is analysed. The study is based on the taper data of Scots pine (Pinus sylvestris L.) stems. According to the results, the use of the mean of butt and top diameters in the volume determination under Finnish condition causes a positive error in small stems. If the stems are so big that the butt portions of the stems can be used as saw logs, the remaining top bolts, used as pulpwood, are estimated to be smaller than they are in reality. Accordingly, there is a negative error.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

In this literature review some error possibilities in the measurement of solid volume of logs and pulpwood are discussed. Although both underestimation and overestimation can occur for various reasons it seems likely that in the stereometric measurement method the real volume is underestimated, at least when Huber’s formula is applied, and the respective middle form factors are too low. Numerous results of empirical investigations are presented in the paper, too.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

Photosynthesis and dark respiration in five families of autochtonous Norway spruce (Picea abies (L.) H. Karst.) and in seedlings from twenty Finnish stands of Scots pine (Pinus sylvestris L.) were investigated in constant environmental conditions. Values of CO₂ exchange were compared with the height growth and weight of seedlings in Norway spruce and with the weight alone in Scots pine. No statistically significant differences were found in CO₂ exchange among progenies or stands. Photosynthetic efficiency and photosynthetic capacity showed a positive correlation both in spruce and in pine. Growth and net photosynthetic capacity were linearly and positively correlated in pine. Spruce and a higher light compensation point than pine. The use of an open IRGA system with several simultaneous measurements and the trap-type cuvette construction in genetic work are discussed.

The PDF includes a summary in English.

• Luukkanen, E-mail: ol@mm.unknown

About one million hectares of forests are fertilized annually in Finland. The goal of the present study was to find out, by means of calculations, how the profitability of forest fertilization varies with variations in the stage of development of tree crops, the quality of the site and its geographical location. Calculations concerned bot fertilization of forests in mineral soil sites and in drained peatlands. The study is a part of a larger project concerning the order of profitability of different forest improvement measures in different conditions. The problems dealt with in this study were approached from the point of view of national economy.

On the basis of two empirical materials it is shown that there is a high correlation between the stand growth percentages before and after the fertilization. Applying the results to existing yield tables the authors calculate benefit/cost ratios showing the stage of development of the stand, the quality of the site and its geographical location. According to the results, fertilization is more profitable in sites of medium fertility than on poor sites. Profitability decreases rather fast from south to north and with decreasing timber prices. 

The PDF includes a summary in English.

• Keltikangas, E-mail: mk@mm.unknown
• Seppälä, E-mail: ks@mm.unknown

The task of this study was to gather all available information concerning timber-sales behaviour of private forest owners and to try to find the probable trends in this behaviour. The initiative for the study came from the Central Association of Finnish Forest Industries.

In Finland there are areas of timber savings and those of overcutting. These are mainly explained by regional variation in prosperity of forest owners. There are also several individual factors affecting timber sales behaviour. Without major changes in forest policy the annual variation in quantity cut in Finland is increasing and the degree of cutting seem to remain below the allowable cut.

The PDF includes a summary in English.

• Hahtola, E-mail: kh@mm.unknown
• Järveläinen, E-mail: vj@mm.unknown
• Reunala, E-mail: ar@mm.unknown

The aim of the paper was to analyse, using a computer simulation technique, the moving distance of pulpwood bolts when direct felling of trees is used and the bolts are gathered alongside the strip road. According to the results, the average moving distance of bolts depends in a complicated way on the usable part of the stem and the spacing of strip road. As a rule, the differences between moving distances of two-meter bolts weighted and unweighted by bolt volume of various trees is 0–16% when the strip road spacing is 30 m the reason being the fact that the heaviest butt bolts are often more far away from the strip road than the top bolts.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

The paper deals with the relationships between macronutrients, ground vegetation and tree crop on a drained peatland area in Central Finland. The former herb-rich spruce swamp was drained in 1930s. The Norway spruce (Picea abies (L.) H. Karst.) stand was established by planting under a nurse crop of birch, which was removed later.

There was a negative correlation between the thickness of the peat layer and the volume and mean height of the growing stock. This was found to depend on the negative correlation prevailing between the potassium content of the topmost peat layer and the thickness of the peat cover. The deficiency of potassium is clearly discernible as deficiency symptoms in the needles, the intensity of which showed a strong correlation with the stand characteristics studied. Among the nutrient characteristics of the topmost peat layer, total potassium and the N/K and P/K ratios showed the closest correlation with the stand characteristics. The communities into which the ground vegetation was divided differed from each other with regard to the calcium content of the peat substrate.

The PDF includes a summary in English.

• Mannerkoski, E-mail: hm@mm.unknown

The material consists of four Scots pine (Pinus sylvestris L.) stems from which 757 samples were taken from various heights and distances from the pith. According to the results, the number of rays and their sizes are greater at the stump level than higher up in the stem. The size increases, and the number decreases on moving from the pith outwards. However, there are differences between stems as regards the variation model. The ratio between the number of fusiform rays and that of uniseriate rays seems to be lower than anticipated earlier, about 1:40–1:50. The average proportion of ray volume varied from 5.6% to 7.3%.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

The study deals with the variation in the proportion of heartwood  in Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) both within and between stems as examined on the basis of literature. Special attention is paid to an application, in which on the basis of the diameter of pulpwood bolts, efforts are made to predict the proportion of heartwood in the total volume of bolts. It is shown that the method, even when based on homogenous material of 564 Norway spruce and Scots pine bolts, easily leads to wrong conclusions concerning the proportion of heartwood.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

A growing stand of Norway spruce (Picea abies (L.) H. Karst.) marked for cutting was investigated in the winter of 1971–72 in Helsinki in Southern Finland in order to determine the economic loss caused by decay. Taking a sample from growing spruce trees with increment borer is not a reliable method of determining the frequency of decay. The decayed stems were twice measured for assortment cutting into lengths; the first time disregarding the decay and the second time doing the actual assortment cutting according to the grade of timber. The direct economic loss caused by decay was 13% of the price for standing timber. The indirect loss may be as great as the direct loss.

The PDF includes a summary in English.

• Kallio, E-mail: tk@mm.unknown

The possibilities of using a pot method to determine the need for fertilizer application were studied. Seedlings of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) were grown in peat samples that had cylindrical shape with a diameter of 25 cm and height of 35 cm. The samples represented three different peatland types, and were fertilized with two levels of phosphorus, potash and nitrogen. Two transplants were planted per pot. The development of the seedlings was followed for three years.

Phosphorus seemed to be of greatest importance for the growth of the seedlings, but nitrogen was also required in the poorest peatland type. Potash did not give statistically significant results. NPK application gave the best response. The usability of the method was studied by following the development of the roots. It seemed that the diameter of the pots was too small and restricted the growth of the root systems.

The PDF includes a summary in English.

• Erjala, E-mail: pe@mm.unknown
• Saramäki, E-mail: js@mm.unknown

The article is a report of a study tour of five Finnish foresters in Germany on September 27 – October 2. 1971. As in most industrial countries, the recreation use of forests is rapidly expanding and, therefore, its needs are considered in the management of forests. Two examples of intensively used recreation forests are described, Schönbuch near Stuttgart and the Bavarian Forest National Park at the Czechoslovakian border. These forests are effectively used for both timber production and recreation at the same time. Some other effects of urbanization on forests also are discussed in the article.

The PDF includes a summary in English.

• Mikola, E-mail: pm@mm.unknown

The material of 78 damaged Norway spruce (Picea abies (L.) H. Karst.) trees was gathered in Southern Finland in order to clarify the advance of decay. The harvesting which had caused the scars had been carried out 12 years earlier and at the moment of the investigation the growing stand was 110 years old. It was noticed that the variables used could explain only a few per cent of the variation of the advance of decay. It was concluded that the only important thing in practice is whether the injuries are in roots or in stems.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

The Finnish forest industries have doubled their use of wood raw material during the past two decades. The average annual overcut of 4.0 million m³ in 1960–64 has been turned into an average annual surplus of 2.7 million m³ in 1965–69. By 1974 industry’s requirements for domestic roundwood would increase by about 6.3 million m³, if all new capacity can be taken into full production. The MERA allowable cut, if realized, would leave a 1.5 million m³ annual surplus in the forest balance in 1974. Less intensive forestry programs would mean a 1.5 to 4.4 million m³ overcut in 1974.

The PDF includes a summary in English.

• Linnamies, E-mail: ol@mm.unknown

The mobility of logging tractors was tested in the winter 1969 on difficult snow conditions to gather information for planning of logging operations and for logging machinery design. The tractors tested were Clark Ranger 666, Timberjack C, Valmet Terra, Ford Brunett 5000, Fiskars 510, BM-Volvo SM 660, BM Volvo SM 661, Ford Country 6, MF-Robur I and BM-Boxer T-350.

According to the results, there is a preference of tracked vehicles in difficult snow conditions compared to wheeled tractors. Ford Country with long and bearing full-tracks proved to have the best mobility. On downhill grades it was found significant differences between three-quarter-track-tractors and skidders, although the performance on level ground and uphill grades was relatively similar. The tracked vehicles can easier move on the packed snow layer and reach a higher speed.

The driving speed does not increase significantly until the density of snow has entirely changed through getting wet. Wet top layer of snow affects positively on driving, because it increases packing of the snow. Increasing density of the snow improves especially the mobility of broad-tired wheeled tractors. To be able to predict the driving speed of a tractor in winter working conditions one must know the depth of the snow layer and the density of the snow and the grade of the slope. In addition, the passages on the same route and the packing of the snow must be regarded.

The PDF includes a summary in English.

• Silvennoinen, E-mail: us@mm.unknown
• Haarlaa, E-mail: rh@mm.unknown

The aim of the present study was to increase the knowledge of the anaerobic conditions prevailing in virgin peat soils of different kinds, and on the fluctuation of the aerobic limit. Silver rod method was used to indicate anaerobic conditions and to locate the aerobic limit. The material included 18 peatland sample plots on treeless bogs, in pine bogs and in spruce swamps in Southern Finland. Observations of the discoloration of the silver rods and measurements of ground water level were made from 8 June to 13 August 1968.

The results show that the location of the aerobic limit is dependent of the depth of the ground water table, and usually lies 5–15 cm above the ground water table. Down to 10–20 cm below the aerobic limit, where it reaches maximum, the rate of decomposition of sulfurous organic matter is positively correlated with the distance from the aerobic limit. Deeper it gradually decreases, and in the depth of 25–35 cm no hydrogen sulphide seems to be released.

In the forested peatland types the volume of the growing stock and the increment were dependent on the depth of the aerobic limit only when nutrient content and pH of the peat was more or less constant. Where the aerobic limit was close to the ground surface but the nutrient contents were relatively high, the volume of the growing stock may be comparatively high. Birch (Betula sp.), better than the conifers, is able to stand conditions poor in oxygen. The growing stock was poor in sites where the aerobic limit was near the ground surface, but the nitrogen and phosphorus contents were high, or vice versa. Consequently, aerobic limit is of great importance as an indicator of site quality.

The PDF includes a summary in English.

• Lähde, E-mail: el@mm.unknown

The goal of this study was to develop a mathematical model for determination of the optimal winching distance in different conditions as based on harvesting costs. In the thinned forest the strip roads are parallel and the winching routes perpendicularly to them. A directed felling of trees is used so that it is easy to make loads to be winched. The stems can also be prepared to timber assortments on the stump area and gathered to loads for skidding alongside the winching routes.

After winching the timber is transported using a forwarder mowing on the strip roads. If the stems have not been bucked in the forests, they are to be prepared to timber assortments before the following transportation, because the problem of turning whole stems in a thinned forest has not yet been solved.

In the mathematical model the formation of the costs was described using 18 variables of which 15 had an effect on the optimum winching distance. Some empirical values were estimated concerning these variables, and the corresponding optimum winching distance were computed. The optimum was mainly determined by the quantity of timber harvested per unit area, the size of the winching load, the regression coefficient of the times which were depended on the winching distance.

According to the model, the deviation from optimum winching distance does not cause a very great change in the analysed total costs. When the winching distance is longer, the increase of the costs is smaller than if it is shorter than optimum. In general, the increase of the costs was so small that in practice one obviously can be satisfied with rather approximate methods in determining the suitable winching distance.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

Field experiments of Scots pine (Pinus sylvestris L.) was established by planting seedlings grown from seeds collected from open-pollinated plus trees throughout the country. The 36 progenies represented were planted in 4 blocks as 2+2 transplants in 1960. The main characteristics of the seedlings were measured in 1966 and 1968. Considerable damage had been caused to the stands by moose (Alces alces) and Melampsora pinitorqua Rostr., consequently, therefore, only normally developed seedlings were measured.

Highly significant differences between progenies were found in the number of branches in 1968 and in the ratio of height of tree to the length of the longest branch. In 1968, the differences in height between progenies were not significant, but there were significant differences between blocks both in tree height and length of terminal shoot. Obviously, the edaphic heterogeneity of the site has influenced mainly the juvenile growth of the plants, because in the length of the terminal shoot there could be seen also significant differences between the progenies. There were no significant differences between the progenies in the length of the longest branch, in the angles of the thickest branches, in stem taper and in the diameter of the thickest branch.

The PDF includes a summary in English.

• Palmberg, E-mail: cp@mm.unknown

The most effective work organization will be used as a goal in minimizing of logging costs. Some type of problem approach is usually utilized. The concept of the ideal system offers a possibility to get guidance in this difficult task. The idea of an ideal system is based on the fact that an ideal system, even imagined, can be utilized for any purpose. There are checklists in handbooks to accomplish the four existing steps: define of function, design ideal, develop optimum and deliver results.

In this paper two special cases are taken up to illustrate the concept itself, and it’s use in design of forestry work organizations. There were found no such reasons which could limit or even prevent the use of this method for forest technological purposes. That is why the author believes the method to give better results than any other customary approach.

The PDF includes a summary in English.

• Haarlaa, E-mail: rh@mm.unknown

The purpose of this study was to explain whether it is possible to affect, in practical working site conditions, by means of logging waste on the strip road, the depth of the track which is formed in terrain transportation and the injuries of the growing stand. Five 20 m long investigation areas with logging waste and five similar areas without logging waste were arranged on one strip road at Teisko logging site in Southern Finland. The logging waste layer was mainly Norway spruce and 10–15 cm thick. A KL–836 B forwarder was used. The type of soil was loam.

The logging waste affected the depth of the track only by decreasing the wear of humus layer. Even decreasing effect of logging waste on the injuries in the growing stand was minor. At Kitee working site in Eastern Finland strip roads were studied. The type of soil was thick, rather mouldered peat. The thickness of logging waste was 3–4 times greater than in Teisko, mainly spruce. A Volvo Nalle SM 460 forwarder was used. The effect of the logging waste on the depth of the tracks was clearly to be noticed. On basis of the appearance of the tracks one could assume that the difference was due to different wear of the humus, and not so much due to the quantity of logging waste that improves the carrying capacity of terrain.

In some extent logging waste was also found to affect the amount and quality of tree injuries. In practical working conditions, the importance might be small, since in the experiments an unrealistically great amount of logging waste was used.

The PDF includes a summary in English.

• Kärkkäinen, E-mail: mk@mm.unknown

This paper presents the results of a contest performed on behalf of the Finnish bank Kansallis-Osake-Pankki and the Central Forestry Board Tapio on growing trees on peatlands. Over 5,000 sample plots were established on drained peatlands in various parts of Finland. The aim was to achieve a best possible growth of seedling stands on peatland. The factors influencing the growth of 85 best Scots pine (Pinus sylvestris L.) and 60 best Norway spruce (Picea abies (L.) H.Karst.) sample plots were studied.

The height growth of the seedling stands decreased towards the north. Fertilization seemed not to decrease the regional differences; rather on the contrary. On the other hand, fertilization increased height growth, but evidently so that the increase obtained was greater in the southern than in the northern parts of the country. Light fertilization (50 kg/ha of K₂O and 60 kg/ha of O₂P₅) caused a clear increase in height growth while heavy fertilization (100 g/ha of K₂O and 120 kg/ha of O₂P₅), had same effect but to much greater extent than the former. Spruce seedling stands in particular benefitted of the heavy fertilization.

Fertilization did not eliminate the original differences in the quality of the sites in question, but these could still be seen in the height growth after fertilization. The effect of drain spacing on the height growth was not very clear. In dense seedling stands (800 seedlings/ha) the height growth of the dominant seedlings was greater than that obtained in stands of lower density. Hold-overs caused a decrease in the growth of the seedling stands.

The PDF includes a summary in English.

• Heikurainen, E-mail: lh@mm.unknown
• Ouni, E-mail: jo@mm.unknown

An attempt was made to estimate critically the genetic gain in clonal seed orchards of Scots pine (Pinus sylvestris L.) in Finland. The selection differential of Scots pine and Norway spruce (Picea abies (L.) H. Karst.) is calculated on the basis of filed information on selected plus trees which has been kept by the genetic register at the Finnish Forest Research Institute. The differentials were computed as realized differences in height between plus-trees and normal stand characteristics on respectively site class and as a function of age.

The genetic gain in height growth of Pinus sylvestris was computed on the basis of information on selection differential and heritability. This genetic gain is between 2.6–4.4% provided there is no pollen contamination from unknown sources outside the seed orchard. The genetic gain of volume growth in Scots pine is about 7–15%, provided there is no pollen contamination in the seed orchard. However, according to investigations, there is invariably some pollen contamination in this kind of seed orchards. The contamination decreases to about 30–50% as the orchard matures and starts to produce endemic pollen. If the pollination would be entirely due to foreign pollen sources, the mathematically calculated genetic gain would be 3.5–7.5%.

The PDF includes a summary in English.

• Tigerstedt, E-mail: pt@mm.unknown
• Malmivaara, E-mail: em@mm.unknown

The aim of the present study was to establish, by means of planting experiments, the influence of different packing, heeling-in and watering as well as the length of the storage period on the development of Scots pine (Pinus sylvestris L.) seedlings, in all 2,090 seedlings, that had been lifted from the nursery bed in spring. The plants were packed in bundles and into plastic sacks in 1965 (6 storage methods) and in 1966 (3 storage methods). Control seedlings were planted without storing at the time when storage of the test material begun. The plantations were followed 3–4 years.

Storage for two weeks in the different ways and planting without storage gave similar results when seedling survival was compared. Storage in plastic sack proved to be as good as storage in bundles in a cellar, and healing-in in moist soil or in a drain were both usable methods. Watering the seedlings did not improve the results, which indicates that the storage caused no serious lack of water.

After four growing seasons an average of 19,6% of the seedlings of the 1965 experiment died, the bulk of them by the end of the first growing season. Despite control treatment, Hylobious abietis caused serious damages. In the plantations of the year 1966 mortality of the seedlings was under 5% by the end of third growing season. During the first two growing seasons after planting differences in growth of the seedlings stored in different ways could be observed in the plantations of the year 1965, but the differences levelled out later. In the plantations established in 1966 no differences in growth occurred.

The PDF includes a summary in English.

• Räsänen, E-mail: pr@mm.unknown
• Koukkula, E-mail: ak@mm.unknown
• Yli-Vakkuri, E-mail: py@mm.unknown

As Finland has neither coal nor oil resources, it has had to resort to large-scale imports dependant on foreign relations and especially maritime connections. When the outbreak of World War II broke these connections, the state had to institute comprehensive controls and measures to ensure the supply of fuels. The present article deals with the measures taken by the authorities at that time.

Although the danger to Finland of interruption in fuel imports had been pointed out, the Finns had made hardly any preparations to manage on their own. In autumn 1939 there was no reserve stocks and particularly vulnerable was the question of motor fuels and lubricants.

When the Winter War ended in spring 1940, it was realised that special measures were needed. A law was enacted that concerned both the revival of production and regulation of consumption. For instance, every forest owner was notified of his share of the fuelwood logging. The wood processing industry had been accustomed to maintain stocks of wood covering two years’ requirements, but these inventories, too, were depleted by 1944. The law for safeguarding the supply of timber, enacted in early 1945, invested far-reaching powers in the authorities, and the logging plans were exceptionally large in 1945-47. Controls governing forestry and the forest industry were discontinued in 1947.

In Finland it is necessary to maintain a state of preparedness. This applies above all to fossil fuels and particularly oils.

The PDF includes a summary in English.

• Osara, E-mail: no@mm.unknown

Measurement of timber in a vehicle load or in a bundle is best performed at the mill where the measuring of large quantities can be mechanized and sampling is possible. Load measurement methods include calculation of the number of units, measurement of pile volume, weight scaling and determination of solid content in accordance with Archimedes principle by immersion in water. For some timber assortments, load measurement is sufficiently accurate and suitable unit of measure. The accuracy of load measurement can be increased or the result can be converted by sampling to a more appropriate unit of measure.

In load sampling measurement, a sample is taken from the population, and the desired more accurate measurement is made from the sample. The basic measurement for the whole population can be converted into the more accurate measuring unit by means of the ratio between it and the basic measure. Unit, pile and weight sampling can be used. The aim for pulpwood is to calculate the dry matter content without bark, which means that the amount of bark and the dry weight of wood must be determined by sampling.

The size of the sample depends on size of the population, variation of the ratio between the loads, and the accuracy required. As the quantity of wood to be measured decreases, sampling measurement will reduce the measuring costs by up to 80%. In addition, there is saving in costs by rationalization.

The PDF includes a summary in English.

• Leinonen, E-mail: el@mm.unknown
• Rikkonen, E-mail: pr@mm.unknown

The purpose of this study was to answer questions concerning the basic information in planning of timber harvesting, how this information has to be handled, and how the planning of logging has to be combined with other forest management planning.

A deductive research method was used. By analysing a logging plan, prepared for a certain forest area, general conclusions were reached. To prepare the logging plan in connection with the forest management plan, the following information was found to be necessary: boundaries of the area, extent and ownership of the planned area, maps including information of the location of the timber and the conditions for transportation, road network and a reliable picture of the difficulty of the forest terrain.

Based on the material of the present timber harvesting methods it will be possible to predict the logging methods which will be applicable in the near future. The object to be planned has to be divided to operation areas. The amount of manpower and equipment needed can be estimated for each phase of the timber harvesting chain on the basis of the information calculated in this manner. Investments to machines and basic improvement works have to be planned before the effect of planning can be calculated in the logging costs, which are to be minimized. Due to the rapid development of the field, the handling of the material in connection with a forest management plan has to be left partly unfinished since the development of future logging methods cannot be reliably predicted.

The PDF includes a summary in English.

• Haarlaa, E-mail: rh@mm.unknown

Fomes annosus (Fr.) Cke. (now Heterobasidion annosum (s.str.)) has proved highly adaptable to varying conditions. Thus, the fungus is able to alter the pH as well as in alkalic as acid direction according to the original pH-grade. The fungus spreads mainly by basidiospores or by the sterile mycelium, but maybe also by the conidiospores. The fungus has spread through the temperate zone; in the tropical and sub-tropical zone it is found sporadically. There is a mention in the literature of at least 136 species in which it has been found. It is found in hardwoods but is most disastrous in conifers. The economic losses are considered biggest in England, Germany and Scandinavia.

The research has not been able to find a safe way to protect the trees growing on an infected site. The only way to limit the damage seems to be the use of mixed stands. Stump-protection has proved to be a relatively effective way to prevent the spread of the fungus to uninfected sites. The formerly used creosote has been mainly substituted by new chemicals, such as sodium nitrite. They act by altering the stump in a way that is favourable for antagonists to Fomes annosus, such as Trichoderma viride and Penicillium sp., or the recently presented Peniophora gigantea.

Although the fungus is found in many tree species, there is a difference in the relative resistance of different species. Among the conifers, the Abies-species (with exception of Abies grandis, A. alba and A. sachalienensis) are considered comparatively resistant. The species of Larix and Pseudotsuga are more resistant than those of Picea and Pinus.

The PDF includes a summary in English.

• Palmberg, E-mail: cp@mm.unknown

The objective of this investigation was to study the influence of stand density of white birch (Betula pubescens Ehrl.) on the minimum temperatures in the stand during the growing season, and the actual minimum temperatures of the leading shoot of Norway spruce (Picea abies (L.) H. Karst.) seedlings growing in the open. The 40-year-old uniform white birch stand was situated in 142 m above the sea level in Southern Finland. The stand was treated with thinnings of three different densities in 1961.

Air temperature was recorded in four sample plots at heights of 0.1 m, 0.5 m, 1.0 m, 2 m and 4 m. In the stand of moderate density, temperatures were measured at heights of 6.0 m, and in the stand of full density at 6.0 m, 8.0 m and 10.0 m.

The temperature differences between stands of various densities proved to be rather small. Especially the thinnest stand differed very little from the open area. The soil surface has in all cases been warm compared with the higher air layers indicating meadow-fog-type by Geier (1965). On cloudy or windy weather all the temperature profiles in the various stands resembled each other. The difference between the air temperature and temperature of the spruce shoot was greatest at midnight and decreased steadily thereafter.

The problem in using shelter stands for spruce regeneration areas is that optimum shelter stand density is difficult to define. Already a thin shelter stand causes drawbacks to the young seedlings, but in order to be effective enough against early frosts, the shelter stand should be comparatively dense.

The PDF includes a summary in English.

• Leikola, E-mail: ml@mm.unknown
• Pylkkö, E-mail: pp@mm.unknown

The technical term reduced yield stands – sometimes reduced yield soils – is widely used in the Finnish forest literature. However, there is no clear definition of the notion reduced yield and no explanation of how this notion is measured in the classifications. Some committee reports and bill proposals and some laws and statutes use the reduced yield forest soil. No definition can be found. In my opinion the term reduced yield forest soils ought to be completely abolished until forest soil experts can perhaps define what it means, if they consider such a concept useful.

Explanations for the term reduced yield stands can be found in the descriptions of classification systems of stands. According to them, the criterion is partly silvicultural (site, species of tree), partly mensurational (volume, sometimes growth), partly economic. No explanation is found as to how the economic aspect is measured, nor about the limit of a full yield and reduced yield.

In my opinion such a term is confusing. I therefore suggest that the term reduced yield stand ought to be abolished. If something is needed instead, I suggest the term understocked stand, defined as a growing stock under certain percentage of a fully stocked stand. The notion of economic reduced yield cannot be generally tied to certain silvicultural and mensurational characteristics of stands. The economic aspect of certain kinds of stands may differ, depending on the owner of the forest and his economic situation, the location of the forest, the composition of the whole forest ownership unit, etc.

The PDF includes a summary in English.

• Saari, E-mail: es@mm.unknown

The paper outlines the information about forest tree nurseries in the Roman Empire, found in ancient writings. According to the author, it cannot be stated that actual forest cultivation was practiced in the times of the Roman Empire, even if tree seedlings were used for a variety of purposes, such as embellishment of cities, parks and gardens, and raising supporting trees in forest vineyards. Nurseries were usually established on farms to fill the owner’s needs. For instance, Gato, Varro, Virgil, Pliny and Colulmella have given instructions about establishment and management of nurseries, and methods to sowing seeds of different tree species. Except for seeds, both root- and branch-cuttings were used in cultivation of trees. Also, grafting was known.

The PDF includes a summary in English.

• Makkonen, E-mail: om@mm.unknown

The present study is an examination of the problems involved in raw-wood inventory from the viewpoint of business economics. The term inventory used here includes the standing timber marked for cutting as well as delivery contracts. The task of inventory is to buffer the differences in timing, locality, quantity and quality caused by purchase, production and delivery processes. The basic problem is concerned with profits.

The basic aim is to keep the inventory small. Its limits are determined by comparing the storage costs and costs of shortage. The costs may be decreased without risking the reliability of deliveries by technical development and road improvement, which also decrease dependence on the seasonal variation of harvesting of timber. A model based on present practices, statistics and practical experiences can be used to calculate different alternatives. The volume of purchases, felling, deliveries, transportation, and differences in quantities and transfer is used to estimate the target level of the inventory. It forms a forecast which the future performances can be compared to. In addition to monitoring turnover rate of the total inventory and capital tied to the inventory, also the exceptions in structure, time and quantity of the inventory and the factors changing it should be monitored. A special difficulty in timber inventory book-keeping are the continuous variations in the measured volumes even if no loss occurs.

The PDF includes a summary in English.

• Einola, E-mail: je@mm.unknown

The aim of this paper was to shape and analyse certain alternatives in the development processes in the organization chains of Finnish forestry. The material was collected by analysing market structures and characteristics of competition with regard to raw wood and forest industry products.

The paper presents two alternative ways to rationalize the organization chains between the forest owner’s organizations and forest industry. In the price mechanism of raw wood originating from Finnish private forests there there has been increasing influence of the central organizations of the private forest owners and forest industry. In their relationship, the model of bilateral monopolistic competition can be chosen as a conceptual framework.

Under bilateral monopoly price is fixed as a result of negotiations between competitive parties, and the position and tactics within the negotiations are of great importance for the negotiating parties. Because of the competition, Finnish forest industry cannot compensate the increase in the production costs by raising independently the export prices of its products. This and the fact that the annual earnings of forest workers are fixed by law to the earnings of the workers in wood-processing industry, will cause pressure on stumpage prices.

In the paper two schemes are outlined. In the Scheme 1 a development alternative is described in which the organization chain of private forest owners is supposed to develop to the industry growing direction. In the Scheme 2 the organization chain of private forest owners is supposed to develop to the organizational orientated direction.

It is concluded that as long as the forest owners’ organizational orientated central organization is too weak to form a monopoly as counterweight to the monopsol of forest industry (except the industries of forest owners), it will consider the industry growing direction superior to the organizational orientated alternative.

The PDF includes a summary in English.

• Rinkinen, E-mail: ir@mm.unknown

The present study gives an account of the dependence prevailing between the actual volume of timber crops, and, on one hand, the sum of cylindrical volume of individual trees, and on the other hand, the utilization per cent. This dependence is rectlinear if the volumes in question are calculated on a running-foot basis. The cylindrical volume of individual trees was calculated on the basis of cross-section area at breast height and the height of the trees. On the basis of the results, it seems that it is possible to simplify timber measurement.

The PDF includes a summary in English.

• Nisula, E-mail: pn@mm.unknown

The paper studied the effect of felling time and conditions in the forest depot of timber to damages caused by spruce ambrosia beetle (Trypodendron lineatum Oliv.) to coniferous timber with bark, both experimentally and observing forest depots in Finland. Effects of fellings was studied by studying the abundance of the beetles in logging residue.

The results show that the spruce ambrosia beetles favour timber felled during the late autumn and winter, stored in a shaded place in the forest. In addition, new spruce stumps maintain and increase the beetle population. Fellings in the forest will increase population during the next year and cause damages in forest depot of timber nearby, because the insect breeds in the stumps. The experiments showed that it is possible to diminish the damages caused by the beetle to timber with bark by spraying with insecticides, and timing the fellings and transport of timber so that there is no timber in the forest in the spring during the time when the insect swarms.

The PDF includes a summary in German.

• Löyttyniemi, E-mail: kl@mm.unknown

The aim of this present study was to elucidate the quality of seed of foreign tree species grown in Finland, and the factors which have affected the quality of the seed yields. Due to the smallness of the material, however, no far-fetching conclusions can be drawn. The bulk of the seeds were collected in the fall of 1964. The samples of seeds were X-rayed and their classification to empty seeds and full seeds of four quality classes was done on the basis of the anatomical structures. The species studied (a total of 34 species) belonged to the following genera: Abies, Chamaecyparis, Larix, Picea, Pinus, Pseudotsuga, Thuja and Tsuga.

The percentage of empty seeds was throughout quite high. The reasons for the generation of empty seeds probably originate from the special nature of the stands from which the seeds were collected. As a rule, the stands were young and small in area, which may have caused weak pollination and self-pollination leading to embryo mortality. Also, insect damages were observed.

Seeds with albumen still discernible, although the embryo had died, occurred to some extent. In some Larix species, even the bulk of the seeds recorded as full belonged in this group.

The ripening of seeds with embryos was quite successful in spite of the fact that the temperature sum of the year of ripening was slightly below the average in Finland. For instance, all Abies species ripened almost completely.

According to the results, it can be expected that the tree species examined in this study are able to produce rich yields of good-quality seed in Finland, provided that the ovules are well pollinated and self-pollination does not take place to a large extent.

The PDF includes a summary in English.

• Tiililä, E-mail: pt@mm.unknown

The purpose of this investigation was to study the felling volume and its structure in the State forests of Finland. Special attention was paid on the proportion of waste wood within the felling volume. This information was in demand for the general plan of the State forests that was being prepared at the same time. The survey was performed using a sampling method, and it represented the districts in the northernmost Finland, Ostrobothnia, Eastern Finland and Western Finland of the Forest Services.

The proportion of merchantable timber of the total felling volume was lowest in the northernmost Finland, less than 2/3 of the total cut. In Ostrobothnia the share was ¾, Eastern Finland 4/5 and in Western Finland 5/6. When the tree species were compared, the proportion of waste wood was largest in broadleaved trees, especially in the Northern Finland, while for Scots pine it was lowest. For Norway spruce the share of merchantable timber is markedly lower in the northernmost part of the country, where, for instance, decay increases the proportion of waste wood. For birch, demand of wood influences most the proportion of waste wood.

In general, the proportion of waste wood and merchantable timber in the felling volume was influenced by changes in the demand of timber, structure of the stands, and the felling method. The demand of the timber assortment affects most in the amount of waste wood. The more valuable the timber assortment is, the less waste wood is left in the cutting area.

The PDF includes a summary in German.

• Kangas, E-mail: yk@mm.unknown

Stand precipitation and stemflow studies became necessary in connection with hydrologic studies, for instance, to explain the deviations resulting from rains in the ratios between the water content of peat and the groundwater level, throughfall during rains of variable heaviness, and effect of stand treatment on soil moisture level. In this project the distribution of rainfall in stands differing in species composition and density was studied in Central Finland in 1963–1965 in fifteen stand precipitation sample plots. In addition, rain gauges were situated under individual Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) H. Karst.) and birch (Betula sp.) trees.

The average precipitation in the open was 4.8 mm, the corresponding precipitation in the stand was 77% for birch, 71% for pine and 62% for spruce. Measurements of stemflow from individual sample trees showed that less than ¼ mm (about 1.5%) during a 15 mm rain in a pine stand. In the spruce stands stemflow is negligible. A part of the sample plots was in drained peatlands with a dense vegetation of small shrubs. The shrub layer retention was about 10% even during heavy rain. In a small forest clearing, the bordering effect of the forest was seen up to the distance of 5 metres from the edge of the forest. During the period of study, on an average 3% more precipitation was recorded in the clearing than in the open, the difference being probably due to the stronger wind effect in the open.

The PDF includes a summary in English.

• Päivänen, E-mail: jp@mm.unknown

The aim of this project was to investigate the cellulose decomposition rate in the soil on the ecological conditions created by different tree species, particularly birch (Betula sp.) and Norway spruce (Picea abies (L.) H. Karst.). Therefore, comparable sample plots were established in adjoining birch and spruce stands. Data on the stands, the vegetation, and the soil in the sample plots were collected. The experiment was carried out in the Ruotsinkylä Experimental Forest near Helsinki in Southern Finland.

Five pieces (3x5x0.15 cm) of cellulose (bleached sulphite pulp) were dried, weighed, and fastened in a row into a nylon bag. The bags were placed into the soil at a slant so that the upmost piece of cellulose was in the depth of 0–1.5 cm and the bottom one 6–7.5 cm. The weight losses of the pieces were measured after periods ranging from 6 to 12 months.

The results show that even within the same forest type, decomposition is much more rapid in birch stands than in spruce stands. In all the stands the decomposition rate decreased rapidly with increasing depth. The difference between birch and spruce stand, as well as the decrease with increasing depth, was probably mainly due to different thermal conditions.

The PDF includes a summary in English.

• Lähde, E-mail: el@mm.unknown

A Timber Scaling Committee was appointed by the Government of Finland in 1959, commissioned with the regulations concerning the scaling of timber and to draw a proposal for their amendments. The commission suggest revision of the regulations in their entire extent. The largest alterations should be made in the act which incorporates the provisions concerning the actual technical methods of procedure in measuring. Thus, also amendments were also posed for the Timber Scaling Law and the law concerning the scaling of timber for the purpose of paying wages.

The inclusion of the setting of the grades and quantities are considered important, since most of the disagreements occurring in measuring are concerned with quality of the timber. Inside of the sphere of application of the law would also be settling of the problems of the quality, and the measuring procedure, also when measuring for the purpose of paying wages.

According to the bill, the necessary number of official scalers and scaling boards would be appointed. The duties of the present officers would be changed. In the boards would be presented sellers, buyers, employers and employees besides the chairman. The freedom of contract in the scaling of timber will be preserved from the present law.

The report includes a bill for the Timber scaling Act, a draft for the timber scaling act, and a draft for an act which includes the timber scaling rules.

The PDF includes a summary in English.

• Puutavaranmittauskomitea, E-mail: –

According to the statistics, the fuel wood consumption in Europe has declined since 1925/1929, when the total fuel wood consumption was 144 million m³. In 1960 the consumption was 108 million m³. Because of insufficient statistics in the early years, the drop may even be larger than shown by the figures. The aim of this paper is to assess what part of European fuel wood removals in 1960 could be used for industrial purposes by 1975.

It was estimated that in 1975 the use of fuel wood in Europe will be about 45–55 million m³ less than in 1960 and about 10 million m³ of this amount will consist of coniferous species. It is believed that about 45 million m³ could be transferred to industrial use by 1975, and 55 million m³ is supposed to be the maximum reduction achievable by 1975. The estimates are based on the revised European fuel wood removal figures.

The new European timber trends and prospects study reveals a shortage of small-sized coniferous wood of about 25–43 million m³, depending on whether the exports from Europe are curtailed or not. The decrease of coniferous fuel wood of 10 million m³ could almost entirely be transferred for the use of industry.

A more important question is, is there demand for the extra small-size broadleaved wood. It is important to note that there is no longer any technical limitations on the use of this kind of wood for producing pulp, paper paperboard and wood-based panel products.

Fuelwood is often collected by the farmer and used near the farm. If the wood is to be used in the industry, harvesting and transport costs need to be decreased. However, productivity of the logging and transportation may be significantly improved by cutting the trees into longer lengths and professional harvesting. About 40% of the potential transfer of fuelwood to industrial uses is concentrated in Finland (7 million m³), France (5 million m³), and Italy (7 million m³). Other countries with significant potential shifts could be Romania, Spain and Yugoslavia.

The PDF includes a summary in French, German, Dutch, Russian and Finnish.

• Roitto, E-mail: yr@mm.unknown

The Economic Council asked Heikinheimo, Holopainen and Kuusela to prepare a report on the development of Finland’s forest resources up to the beginning of the next century. The expansion of forest industry beyond the level foreseen in earlier forecasts, the large-scale removal and neglect of the basic improvements required have weakened the condition of the wood production to such an extent that extensive measures are needed to ensure the continuity of the supply of wood. The results of the calculations are formed in three separately analysed alternatives.

Alternative I: Realisation of the Teho programme and the removal corresponding to it. The development of the growing stock according to the programme would only permit a cut amounting to an annual drain of ca. 51 million m³ up to the year 2000. After that it would be possible gradually to increase the removal. This drain would not itself to utilise fully the already existing production capacity of the industry.

Alternative II: Consequences of the predicted removal if the Teho programme is realised as such. The wood utilization forecast based on the premises given to the team show that the annual drain will grow in 1964–1975 from 52 to 58 million m³, and thereafter by 0.5% annually. This would lead to over-cutting, and exhaust the present growing stock by the turn of the century. If annual total drain of ca. 58 million m³ would after 1975 be sufficient, exhaustion of the growing stock would be postponed for 4–5 years.

Alternative III. Teho programme expanded in conformity with the removal forecast. A new programme is proposed, which includes, among others, large scale fertilization of fully grown firm forest land at about the rate of 100,000 ha/year, intensified artificial regeneration, assurance of the supply of planting stock and seed, increase of forest drainage from the present 155,000 to 250,000 ha/year by 1970, site preparation of the cutting areas for artificial regeneration, increase of tending or seeding stands to 300,000 ha/year, replacement of fuelwood by other fuels, increase of wood import and new forest roads.

• Ervasti, E-mail: se@mm.unknown
• Heikinheimo, E-mail: lh@mm.unknown
• Holopainen, E-mail: vh@mm.unknown
• Kuusela, E-mail: kk@mm.unknown
• Sirén, E-mail: gs@mm.unknown