Current issue: 58(4)
The study deals with the interaction of various soil preparation and reforestation methods. The most favourable time of the year for broadcast sowing and the effect of stabilization after soil preparation on restocking were studied as special problems.
Prescribed burning, scalping and disc ploughing made a better combination with sowing than planting, and ploughing better combination with planting than sowing. The longer the period was between sowing and germination the fewer seedlings emerged. The best stocking was clearly resulted with sowing in June. Stabilization of soil after preparation had a negative effect on reforestation results.
The PDF includes a summary in English.
Prescribed burning has reported to avail forest regeneration, for instance, by releasing nutrients for the use of seedlings, changing the pH of the soil and decreasing competition of ground vegetation. The aim of the study was to find out if the effects could be verified. Sample plots were measured in the experimental area of Tuomarniemi, in Central Finland, both in previously burned and untreated seedling stands and young forests. The main species in the sample plots was Scots pine (Pinus sylvestris L.).
According to the results, prescribed burning prepares the soil for regeneration. Germination percentage of the seeds is higher on the burned soil. All the species, Scots pine, Norway spruce (Picea abies (L.) Karst.) and birch species (Betula sp.) grow faster. Prescribed burning increases the amount of birch seedlings by improving its regeneration compared to unburned sites. The seed trees survive burning better if they are tall and have short crown, and have thick bark. In general, prescribed burning improves regeneration in seed tree stands.
The article includes a summary in German.
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 preparation and forest regeneration methods of a burned area.
Silva Fennica issue 46 includes presentations held in professional development courses, arranged for foresters working in public administration in 1937. 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 forest regeneration on poor forest sites.
Silva Fennica issue 46 includes presentations held in professional development courses, arranged for foresters working in public administration in 1937. 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 effect of properties of soil on forest regeneration.
The aim of the study was to follow development of vegetation in dry upland forest sites after forest fire. The sample sites were situated in the counties of Muonio, Kolari, Sodankylä, Pelkosenniemi, Savukoski, Kemijärvi and Salla, in the northernmost Finland.
The growth of plant communities can arise either from the vegetation and seeds that survived the fire, or from seeds that spread from the surrounding areas. The development of vegetation in the burned areas was unexpectedly independent of the surrounding areas, which indicates that role of the seeds from the outside of the burned ares is small. The occurence of different species of lichens, moss, scale moss and vascular plants in the burned areas are described in detail. The development of vegetation was strongly dependent on the forest site type. The thin humus layer of Cladina site type burns usually evenly, and also the vegetation develops more evenly than in the more fresh site types. Vegetation typical for burned areas was fully developed within 10-15 years, and after 25 years it began to resemble the vegetation of Cladina site type forests. The ground vegetation of Calluna type burned area was more patchy. It developed quicker than in Cladina type. Absense of lichens made it seem more fertile than is usual for Calluna type. The humus layer of Empetrum-Myrtillus site type burned unevenly, and if the area was lightly burned, the vegetation recovered quickly. The vegetation was often patchy.
The PDF includes a summary in German.
The issue 39 of Silva Fennica includes presentations held in professional development courses in 1935 that were arranged for foresters working in public administration. The presentations focus on practical issues in forest management and administration, especially in regional level.
This presentation describes the forest management work in the state forests.
Prescribed burning has been used to treat the mineral soil sites, but the method has been little used in drained peatlands. The course and methods of prescribed burning in drained peatlands, and the effect of burning on sprouting of broadleaved trees, growth of ground vegetation and regeneration of Scots pine (Pinus sylvestris L.) by sowing was studied in drained pine bogs in Southern Finland. The top layer of the peat was mostly Sphagnum peat. The material included a prescribed burned 12 ha drained peatland area in Tuomarniemi district, in addition to which ten previously burned areas were investigated.
The burning had succeeded mostly well, but also unsuccessfully burned sites were observed. Estinguishing of the fire was easy, and no peat fires occurred. The fire burned only the logging residue, ground vegetation and the dry top layer of the peat. The roots of brushwood and grasses survived in the peat that insulated the top layer from the heat. For instance, the abundance of cloudberry (Rubus chamaemorus L.) increased after the fire. Similarly, burning did not affect sprouting of the stumps of downy birch (Betula pubescens Ehrh.). It cannot thus be used as a method to restrict the growth of coppice in regenerated areas. The seeds of Scots pine germinated well on the burned surface. 46% of the seeds developed to seedlings on sphagnum-shrub vegetation and 16% in feathermoss-shrub vegetation.
The PDF includes a summary in German.
The regeneration of forests in Hämeenkangas area in Southern Finland has been difficult due to various damages from the middle of the 1800s. Few seed trees were left in the area, and artificial regeneration has been used since 1880s. The area became an experimental area of the Forest Research Institute in 1924. The aim of the study was to survey the area before it was transferred to the Finnish Defense Forces.
The original Scots pine (Pinus sylvestris L.) forest of the esker area suffered from many forest fires. The total area is 13,000-14,000 ha, of which the experimental forests of Forest Research Institute cover 6,000 ha. The area is dry upland forest, and drought affects the survival of germlings. Soil frost is a major cause of loss of young seedlings. Sowing method affects the early development of the seedlings. Band sowing proved to be the best method regarding the soil frost. A total of 39 different harmful insect species, 8 pathogen species and 7 other causes of damages have been detected in the area.
The development of seedling stands follow a certain pattern, reported also in other studies. Many of the pine seedling stands develop well until they reach a certain height. After that seedlings begin to suffer from damages, but after reaching another stage develop normally. The damages affect the height growth of the seedlings. Some common damages are caused by Pissoides weevils, needle damages caused by certain beetles, shoot damages by Evetria resinella, and pine blister rust (Peridermium pini and Cronartium flaccidum).
The PDF includes a summary in GermanTotal of 1,305 forest fires was ignited in 1925-1934 in the forests insured by the Metsänomistajain Keskinäinen Metsäpaloapuyhdistys (The Forest Owners' Mutual Forest Fire Insurance Company and the Keskinäinen Vakuutusyhtiö Sampo (The Sampo Mutual Insurance Company). The variation was large: from 34 fires in 1928 to 362 fires in 1933. The forest fires were most abundant in the county of Oulu and Häme. The average size of the burned areas varied from 2.4 hectares to 30.5 hectares. The area of forests that had forest fire insurance increased steadily from 2.2 million hectares in 1925 to 3,7 million hectares in 1934.
The PDF includes a summary in German.
The study is based chiefly on statistics of forest fires in the state forests in 1911-1921, published in the annual reports of Board of Forests (now Metsähallitus, Forest Service). Forest fires burned 37,200 hectares of forests in the state forests in 1911-1921. In Southern Finland the number of fires was 795 and in the Northern Finland 610. The frequency of forest fires is higher in south because of the denser population in the area. The average forest fire ranged 118 hectares in Southern Finland and 39 hectares in the north. Fires broke out most often because of careless use of fire. Weather conditions and the type of the forests influenced the risk of fire. In the north, risk for forest fire is lower because of the high proportion of peatlands. Only 14% of the fires burn the trees of the stand. In Southern Finland 50% of the fires and in Northern Finland 42% of the fires damage only part of the stand. Rest of the fires were surface fires that do not burn the trees. The value of damages by forest fires in the state forests in 1901-1922 was annually in average 139,400 Finnish marks.
The PDF includes a summary in English.