Current issue: 56(4)
Under compilation: 57(1)
A Gremmeniella abietina (Lagerb.) race of type A was found to produce pycnidia in cankers of previous year’s shoots (1991) on branches of Scots pine (Pinus sylvestris L.) bearing green needles and living buds in the current-year shoots (1992) with no apparent symptoms of infection by G. abietina. The restricted colonization of green shoots by G. abietina, with only restricted canker development, may indicate that older, slow-growing natural Scots pines of the northern boreal forests resists the fungus well. However, the ability of the fungus to survive and even sporulate in such cankers indicates one way of surviving over consecutive years otherwise unfavourable for it.
For non-industrial private forest (NIPF) owners land with its timber production is an example of a capital asset. Developments in the asset’s value and yield depend not only on forest management but also on other factors that the owner cannot control, for example timber prices and the production circumstances, such as soil and climate. One important basis for decision making related to management strategy and, in the short run, to cutting and silvicultural activities is economic analysis and accounting. The owner has to decide whether to invest more in his property (planting, cleaning, building of forest roads) or disinvest (sell timber or the holding). He has to find ways to increase revenue and cut costs.
However, generally accepted accounting practices for NIPF owners are lacking. Applying business economic accounting principles and forestry accounting traditions, we outline a proposal for a profit and loss accounting and balance sheet for NIPF holdings with a view towards increasing economic awareness among private owners. Key concepts are net profit of the enterprise and calculated profit of the property. Other profit measurements that are used are gross margin, forestry margin, operating margin and operating profit. Calculated profit is based on adjusted net profit. The main concern, however, is to consider the change in the holding’s market value caused by changes in stock volume, quality and price. The contents of the accounting framework development here are applied to three management strategies. The return on investment (ROI) of forestry is compared with other investment alternatives.
53 genotypes of embryonal suspensor masses (ESMs) rescued from mature seeds of Norway spruce (Picea abies (L.) H. Karst.) were examined for their pattern of growth and development under standardized culture conditions in vitro. Patterns were classified according to the colour of the colonies grown in darkness, clarity of cell masses and proembryos in the mucilaginous ESM, surface boundary topology of colonies, structure of suspensors, growth rate of the ESM, and recovery of mature embryos.
Five distinctive major growth patterns were observed among ESM colonies under standardized culture conditions. The multiplication of proembryos and early embryos by cleavage and budding polyembryony was the main factor contributing to proliferation and colony growth and further determined the morphology of the colonies. Callus and teratological structures were induced from early embryos by changing the standardized culture conditions i.e. inadequate subculture, excessive dose of 2,4-D in the medium and premature exposure of the colonies to light. Results enable the selection of ESM genotypes for the predictable recovery of mature somatic embryos.
Forest ecosystems may accumulate large amounts of nitrogen in the biomass and in the soil organic matter. However, there is increasing concern that deposition of inorganic nitrogen compounds from the atmosphere will lead to nitrogen saturation; excess nitrogen input does not increase production. The aim of this study was to determine the long-term changes caused by nitrogen input on accumulation of nitrogen in forest soils and in ground vegetation.
The fertilization experiments used in this study were established during 1958–1962. They were situated on 36- to 63-year-old Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) stands of different levels of fertility. The experiments received nitrogen fertilization 5–7 times over a 30-year period, and the total input of nitrogen was 596–926 kg/ha.
Nitrogen input increased the amount of organic matter in the humus layer and the nitrogen concentration in the organic matter. Furthermore, the total amount of nutrients (N, P, K, Ca and Mg) bound by the humus layer increased due to the increase in the amount of organic matter. However, nitrogen input decreased the biomass of ground vegetation. The nitrogen concentration of the plant material on the nitrogen-fertilized plots was higher than on the control plots, but the amount of nutrients bound by ground vegetation decreased owing to the drastic decrease in the biomass of mosses. Ground vegetation does not have the potential to accumulate nitrogen, because vegetation is dominated by slow-growing mosses and dwarf shrubs which do not benefit from nitrogen input.
The amount of carbon (C) stored in wood products manufactured in Finland was calculated with the help of a model using wood harvesting statistics, product flows and lifespans in order to study how much C could be set aside from the atmospheric C cycle outside the forest ecosystem. The calculations showed that on the average 9.9 Tg C/a was in harvested timber in 1986–1991 in Finland. C emissions of timber harvest and transport were 0.1 Tg C/a. In production processes about one third of the C bound in in timber was released into the atmosphere, but two thirds was still bound in products. After 50 and 100 years, more than 40% and 33% of the C initially in products was either in products still in use or disposed to landfills. The wood product C storage was most sensitive to landfill decay rate and to the burning of abandoned products for energy, but not to the same extent to the length of the lifespan of products.
Damage on Scots pine (Pinus sylvestris L.) caused by Gremmeniella abietina (Lagerb.) Morelet was assessed in the summer of 1992 in 67 stands in eastern Lapland. The area and severity of damage were smaller and lighter than had earlier been estimated and occurred especially in stands in the first-thinning stage or in middle-age. Significant new infection of 1991 occurred in stands previously heavily infected by G. abietina near Kemihaara river, lake Naruska, the Naruska river, the Tuntsa river and lake Vilma. Fresh damage occurred mainly in the lower or middle parts of the Scots pine canopies.