Current issue: 58(5)
Different methods of sowing and planting of Norway spruce (Picea abies (L.) H. Karst.) were compared on fertile sites in North Karelia (62°20’N, 29°35’E, 85–120 m a.s.l.). The planting material were 4-year-old bare-rooted transplants, 2-year-old bare-rooted seedlings, and 2-year-old containerized seedlings raised in plastic greenhouse. The sowing methods were band sowing and shelter sowing. Ground vegetation was controlled during the first growing season mechanically or chemically, or the control was omitted totally.
Planting of spruce gave better results than sowing. After eight growing seasons there were sowed seedlings left in 30% of the sowing pots. The average height of them was 35 cm. Seedling survival was best with large bare-rooted transplants (91%). Survival of containerized seedlings was 79% and of small bare-rooted transplants 71%. The average height of large bare-rooted transplants was 131 cm, of containerized seedlings 86 cm and small bare-rooted seedlings 68 cm.
Sowing is not an advisable method for regeneration of spruce due to the small survival rate and slow initial development when ground vegetation is controlled only once. Also 2-year-old seedlings gave a satisfactory result in regeneration. Seedlings raised in greenhouse were more sensitive to frost damage than seedlings grown on open ground.
The PDF includes an abstract in English.
Containerized tree seedlings will be used on an increasing scale in the future in different parts of the world. There are number of techniques for the production of small one-year-old seedlings but it has not been possible to develop a completely satisfactory methods for large containerized seedlings production. In the long-term development of pine plantations established with containerized seedlings the greatest problem has been deformation of the root system. With a new method, based on a sheet of peat and root pruning, it has been possible to produce conifer seedlings with a good root regeneration potential and favourable morphological root system development. The use of small containerized seedlings allows an increase in planting density without any marked increase in regeneration costs.
The PDF includes an abstract in English.
The Academy of Finland commissioned a review of forest regeneration research. This paper summarises the evaluation. The report deals with the individual research projects and, in addition, the international evaluation group gives several recommendations to develop the forest regeneration research further. The recommendations concern education and training, publications, peer review, experimental design, routine work and extension service, and technology transfer. The paper also includes comments of the Finnish Forest Institute, the Finnish Society of Forest Science and a research scientist on the results of the evaluation.
The PDF includes a summary in English.
Length of the regeneration period is a criterion commonly used for comparing different reforestation methods. The time factor should be evaluated using a realistic system for long-term planning. In this paper the preliminary evaluation is made by simplified calculations based on the development series. The slow regeneration method is assumed to be otherwise equal to the rapid one but it has a 5- or 10-years delay at the beginning, and the rotation is thus the final cutting age plus 5- or 10-years delay. Cost of the time delay is taken to be the difference in reforestation costs that makes the rapid and the slow methods equivalent. Calculations are made using zero costs for the slow method; but if the cost of the slow method increases, the critical cost difference decreases very slowly. The final cutting age and the regeneration method must be decided simultaneously. Therefore, the cost of the time delay is presented as a function of final cutting age. By maximizing the average annual revenue, rotation can be even increased if more rapid but more expensive regeneration method is used.
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 80 includes presentations held in 1952 in the 7th 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 principles of breeding of forest trees and the selection of fast growing, healthy and qualitatively good trees, named plus trees, for seed production in Finland.
Silva Fennica Issue 80 includes presentations held in 1952 in the 7th 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 a field experiment on the use of herbicides to prevent growth of ground vegetation in cutting areas before sowing. The study suggests that the chemicals used in the experiment were not effective enough to prevent growth of ground vegetation in the more fertile lands, but were effective in poorer lands. However, the treatment affected also growth of tree seedlings.
Silva Fennica Issue 80 includes presentations held in 1952 in the 7th 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.
Soil preparation improves formation of seedlings in natural regeneration sites. This presentation describes mechanization of the work using four different machines. According to the study, the effectiveness and quality of the work has improved compared to the earlier machines, and the method is becoming a competitive alternative to slash burning.
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 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 state of forests in Northern Finland, and suggests that fellings are targeted at the oldest forests until the over-presented over-aged forest are harvested. The preferred regeneration method is natural regeneration in most forest types.
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 a study of forest management practices suitable for in Hylocomnium-Myrtillus site type forests, typical for Northern Finland. A special problem for the forest site type is poor regeneration due weak seed production of Norway spruce (Picea abies L. Karst.) and thick moss layer.
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 factors that should be taken into account in forest regeneration.
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 clearing of felling areas.
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 German