Current issue: 58(5)
Articles containing the keyword 'puutavara'
Category : Article
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.
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Mäkelä,
E-mail:
am@mm.unknown
- Ikonen, E-mail: vi@mm.unknown
- Vanninen, E-mail: pv@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.
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Holopainen,
E-mail:
vh@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.
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Kärkkäinen,
E-mail:
mk@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.
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Kärkkäinen,
E-mail:
mk@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.
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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.
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Kärkkäinen,
E-mail:
mk@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/m3, 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.
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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.
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Kärkkäinen,
E-mail:
mk@mm.unknown
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.
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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.
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Kärkkäinen,
E-mail:
mk@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.
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Kärkkäinen,
E-mail:
mk@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.
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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.
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Kärkkäinen,
E-mail:
mk@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.
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Leinonen,
E-mail:
el@mm.unknown
- Rikkonen, E-mail: pr@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.
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Löyttyniemi,
E-mail:
kl@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.
Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.
This presentation describes benefits of the qualitative classification of saw logs to forest owners and forest industry.
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Heiskanen,
E-mail:
vh@mm.unknown
Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.
This presentation describes the uses and principles of different kinds of grading of saw logs.
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Heiskanen,
E-mail:
vh@mm.unknown
Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.
This presentation describes the grading of sawn timber for export and domestic use, and suggests improvements to grading of the sawn products in the saw mills to better answer the needs of export.
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Siimes,
E-mail:
fs@mm.unknown
Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.
This presentation describes the development of standards for timber grades in Finland, and the present quality grades of raw timber for timber sales from state forests.
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Pöyhönen,
E-mail:
vp@mm.unknown
Silva Fennica issue 52 includes presentations held in professional development courses, arranged for foresters working in public administration in 1938. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.
This presentation describes the Timber Measurement Act, adopted in 1938, and its application.
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Mecklin,
E-mail:
am@mm.unknown
Silva Fennica issue 42 includes presentations held in professional development courses, arranged for foresters working in public administration in 1936. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service
This presentation describes determination of stumpage prices in timber sales of the state forests in Finland.
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Mecklin,
E-mail:
am@mm.unknown
The fellings of small timber have been expanded from seasonal to full-year operation in many areas. A time and motion study was conducted on the felling of pulpwood in different times of the year in seven felling sites in the northernmost Finland. The work was payed per one pulpwood bolt. The output of a one-man teams was larger than 2-6-man teams. Teams of even numbers were more effective than teams of uneven numbers. One-man teams were more popular during summer. The output was largest during the summer. In the late summer the results decrease, because barking of trees becomes more difficult. Shortening of daylight hours begin to shorten the workdays in the autumn. In December, the average working days are about 6 hours. Snow and low temperatures make logging and barking more difficult during the winter. The output was lowest in January, despite that work days are 1 ½ hours longer than in December. It is concluded that pulpwood fellings should be avoided from December to March 15. If the fellings are necessary, the wage system should be changed more flexible than at present. The size of cutter’s lots should be adjusted so, that work periods are not too short. Sufficiently big lots save time spent on travelling between the sites and villages.
The PDF includes a summary in German.
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Maliniemi,
E-mail:
em@mm.unknown
Majority of the timber floated in Finland has been floated loose. Repair of the floating channels in the end of 1800s decreased the amount of sunken logs and loss of timber during the transportation. The increase of floating of pulpwood and other small timber has later increased the number of sunken logs. More information is needed on the amount and quality of floated timber, also the floating channels should be classified. A detailed study plan to investigate how big proportion of the timber is lost during floating, which factors influence the sinking of timber, and how the timber dries in the forest depots is presented. A classification of timber by its floatability is presented.
The PDF includes a summary in German.
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Lassila,
E-mail:
il@mm.unknown
Category : Article
Seasonal variation in the sawmill industry of Finland was studied in an investigation based on questionnaires answered by a random sample of sawmills concerning the time period of 1958-1960. The method is described in detail in a separate article in Acta Forestalia Fennica issue 75 no. 1.
The seasonal variations in purchase of roundwood was largest in big sawmills, which purchase the main part of the timber as standing sales and buy most of the wood from the State Forest auctions at the end of September. Also, they can afford to reserve their material earlier than the smaller companies. The saw logs are mainly felled in the winter in Finland because the climatic conditions and availability of labour are best at that time. Small sawmills begin fellings a little earlier than the larger ones.
In long-transport of timber the proportion of floating decreased from 47% in 1958 to 38% in 1960. At the same time, proportion of truck transport increased from 48% to 55%. Small sawmills use almost exclusively land transport. They received almost three-fourths of their logs between January and May, because the sawing is concentrated in the first half of the year. Therefore, floating does not suit for their transport method. The larger the sawmill, the later is the seasonal peak of log deliveries. The output of the big sawmills is distributed more evenly thoughout the year. The smaller the sawmill, the quicker is the turnover of raw material and the smaller the sawlog inventories.
The seasonal variation in output is sharper at small sawmills where sawing is concentrated in the first half of the year. The seasonal peak of the early spring is due to the aim at getting the sawn wood to dry early enough for shipments in the summer. Air drying takes an average of 4 ½ months. Kiln drying is more common at the larger sawmills, and gives them more flexibility. Due to the large seasonal variation in operation, the capacity of the small mills is poorly utilized. Domestic sales of sawn wood levels up the seasonality of the deliveries. Export sales are concentrated at the end and turn of the year. Also, the seasonal peak of expenditure occurs in the winter, but that of income in the summer.
The PDF includes a summary in English.
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Ervasti,
E-mail:
se@mm.unknown
The analysis of costs is the foundation for the efficient management of logging activities. However, there is little research on cost accounting of logging. This article is an overview on harvesting of timber and its cost accounting, concentrating on joint costs. Costs have to be divided on their structural elements and then regrouped according to different accounting needs to be investigated. This investigation bases the structural cost analysis on running booking of costs. Due to the variability of logging, the costs are divided in detail into categories. The costs of logging are classified by their origin into personnel cost, material costs, costs of services, compensation for use, unrequited costs, risks, depreciation and interest. Further, the costs are classified according to the subject and quality of performance, and by location.
The PDF includes a summary in English.
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Einola,
E-mail:
je@mm.unknown
Forest transport of timber in Finland has been arranged as horse haulage during winter time using horses vacant from farm work. Tractors have now begun to replace horses in agriculture, which will lead to shortage of horses for timber harvesting in future. The aim of this investigation was to find a method of mechanized forest transport suitable for Finnish conditions. The method should be provided by an agricultural wheel tractor that is shared with agriculture. It should also be applicable to timber transport of relatively small forest holdings.
A method for time studies of tractor driven timber harvesting was developed. The competitivity of tractor transport of timber against the traditional method was studied in four pulpwood harvesting sites. The results suggest that if the tractor forest transport method in question is to be applied in practice, conditions should first be chosen which favour it most. A tractor forest transport method evolved on the basis of experiments presupposes certain conditions to be successful. These include snow for the construction of the packed-snow driveway, frost to harden the driveway, the location of strip roads in relatively easy topography, and of the main haulage road that is gently sloping in the haulage-loaded direction. The optimal transport distance for this method are about 3-10 km.
The PDF includes a summary in English.
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Putkisto,
E-mail:
kp@mm.unknown
Work studies conducted in Finland and Sweden on forest work have shown that the performance of different workers or even of a same worker vary greatly, although external conditions such as the size and other properties of the trees, weather etc. are similar. It has been decided in the Northern Countries that as it is impossible to assess the working speed of a man, it is not possible to find out the average work performances, not even from long term time studies. The only way is to collect performance statistics.
Metsäteho (Forest Work Studies Section of the Central Association of Finnish Woodworking Industries) has collected since 1946 statistics on the working sites of forest industry companies in different parts of Finland on the preparation on timber. To make it comparable the material has been converted to uniform values by using the ratios given by the work time studies of various forest jobs conducted by Metsäteho. The ratios are necessary in trying to determine average performances by statistical means. The actual length of time each man is at work on different days and the actual number of days is needed, because in Finland the workers can themselves decide fairly freely the length of a working day. In forest work, wages are paid for the quantity prepared, not for time. The statistics collected by Metsäteho include information on the length of the working days, and conditions in each forest, such as the size of the trees, form of stem, branchiness, bark thickness, terrain, density of the forest, weather conditions etc.
The Acta Forestalia Fennica issue 61 was published in honour of professor Eino Saari’s 60th birthday.
The PDF includes a summary in English.
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Vöry,
E-mail:
jv@mm.unknown
Central Association of Finnish Forest Industries decided in 1953 to begin collecting annual statistics of timber transportation of its members. The survey of members covers almost 97% of the timber transportations of the member companies, which have production over 1,000 cu ft. In all 79 companies answered the survey. Their total timber transportation was 166,4 million cu ft in 1952.
The long-distance transportation of saw logs by horse transport directly to the mill or other such location was 1,297 cu ft, by truck transport 42,644 cu ft, by rail transport 6,707 cu ft, and by water transport 115,789 cu ft. The average transportation distance was for horse transport 2.4 km, truck transport 27 km, rail transport 224 km and water transport 209 km.
The Acta Forestalia Fennica issue 61 was published in honour of professor Eino Saari’s 60th birthday.
The PDF includes a summary in German.
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Lindfors,
E-mail:
jl@mm.unknown
Pruning growing trees influences tree growth and value of the wood and yield of timber of the stand. Pruning living branches create open wounds on the stems that can risk the growth of tree species that are vulnerable to injuries. For instance, pruning has been shown to cause decay in Norway spruce (Picea abies (L.) H. Karst.), while Scots pine (Pinus sylvestris L.) can quickly heal over the branch scars. Pruning of living branches reduces the crown, the effect of which remains small if only the lowest branches are pruned. Pruning of dry branches has little effect on the health of the tree. The main objective of pruning is to improve the quality of timber. Knottiness decreases strength and appearance of timber. Pruning increases the yield of knot-free sapwood, which is especially valuable in veneer timber. Pruning is, therefore, at present most suitable for birch and aspen which are used in veneer industry. In both species pruning should be directed mainly to dry branches.
The PDF includes a summary in German.
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Lappi-Seppälä,
E-mail:
ml@mm.unknown
The timber companies began acquiring forest land in 1890s which raised concerns about decrease of the number of private farms and agricultural land, as had happened in Sweden earlier. This was not considered to be a major problem in Finland, but the sale of homesteads on former state lands for sawmill companies was considered to be against their objective. One reason for the sale of farms was the farmers’ poor conception of the value of the land. In 1915 three decrees that restricted the right of companies that use timber to buy land were approved. The article discusses in detail the arguments that led to the legislation and compares it to the situation in Sweden.
A survey was commissioned to study the of landholdings of the companies, and to compare it with farming in private and company owned farms. The article includes a study about individual farms in the municipalities of Multia, Heinävesi, Sulkava, Ruokolahti and Luumäki, and about land use in the areas.
The PDF includes a summary in German.
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Renvall,
E-mail:
ar@mm.unknown
- Boman, E-mail: ab@mm.unknown
The aim of the study was to determine how timber truck transport business succeeds in the competition within its sector, and the effect it has on profitability structure of the sector. Furthermore, strategic groups were looked at in depth, as well as the competitive strategies of the most successful companies and groups of companies. The theoretical competitive strategy was operationalized.
A total of 53 timber truck transport entrepreneurs were interviewed. The average age of the entrepreneurs was 51 years. Of the businesses, 35% were partnership companies, 6% open companies, and 59% self-employed. The business owned an average 1.5 trucks, and at the time of interviewing their average age was four years. Nearly nine out of ten entrepreneurs had no schooling for the line of business, and four out of five had no short-term training. The attitude of the timber truckers toward their activities was more like that of self-employed persons than that of entrepreneurs. A total of 61.5% of them reporter that they carried on entrepreneurship simply to assure themselves a job.
The operational profitability of the sector has been good in the years 1984 to 1990, and the business profitability fairly good. The median equity ratio in the sector has remained at about 20% and the ratio of debts to turnover about 40%. The sector has been more profitable than forest machine contracting primarily due to the barriers to entry into the sector.
Cluster analysis, using Ward’s method, was used for seeking out strategic groups. The lengths of the customer relationships proved a significant barrier to mobility. The most successful business used the competitive strategy of cost weighted focussing. This was done through optimization of the capacity utilization rate and through choice of correct customers. The strategic position for successful business was judged to be good in the future. Success in the future will require above all activeness and innovation ability.
The PDF includes a summary in English.
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Mäkinen,
E-mail:
pm@mm.unknown
The paper is the final report of a study on the estimation of value increment and inherent variables of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) stands. The main aim was to obtain improved criteria for decision-making concerning the priority of stands for regeneration.
The construction of various estimation models and their reliability are discussed in detail. The study, together with some previous papers, has resulted in a system which on the basis of a number of easily assessed stand variables gives for the stands concerned the volume of stems, percentages of timber assortments, stumpage value, volume increment and value increment.
The following examples are given with regard to the practical application of the results, in addition to the determination of the relative maturity of stands: 1) The study of various trends in stand development; the comparison between the volume and value variables. 2) The estimation of timber assortments needed for a cutting budget, trees marked for felling etc. 3) The calculation of the value of forests.
The PDF includes a summary in English.
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Nyyssönen,
E-mail:
an@mm.unknown
- Ojansuu, E-mail: ro@mm.unknown
