The Dominant Coniferous Trees
Forests cover 2.9 million hectares of Latvia’s territory. The area covered by forests varies throughout the country — from approximately 30% in Dobele, Jelgava, Preiïi and Rçzekne districts to more than 60% in Ventspils District. State-owned forests take up 50%, privately owned forests 43% and forests of other ownership take up 7% of the total area.
The LVM administrates and manages 1.65 million hectares of the land of the Republic of Latvia. Forests cover 1.37 million hectares of it. The dominant trees in the forests managed by the LVM are coniferous and they take up 69% of the territory (47% pine and 22% spruce). The rest of the territory is covered by deciduous stands, mostly of birch (24.1%), aspen (2.7%) and common alder (2.5%). There are small stands of hardwood trees (oaks, ashes) and grey alder.
The forest that is managed by the LVM can be divided into pure stands and mixed stands. The major tree species in a pure stand constitute 80% or more of stock volume of a stand. Distribution of trees in mixed stands may differ. The most common pure stands in the LVM forests are pine stands (74%), grey alder stands (57%) and spruce stands (53%). Stands of deciduous trees are far more mixed.
Species Age Class Distribution Has Been Affected by Spruce Plantations
Sustainable management of forest resources and development of new stands are based on forest age class distribution by tree species. Age class distribution in the LVM forests is relatively uneven. There are relatively large areas of pine, which are 40 years old or older, but spruce dominates in younger forests.
The proportion of young stands of birch is relatively small and that can be explained by the opinion predominating in the Soviet Union time — there will be no demand for hardwoods.
Although there is a marked difference between the areas covered by young stands of spruce and stands of birch at present, the LVM plans to reduce this disproportion both by afforestation of birch on the land not used for agriculture and by investing in thinning of naturally regenerated deciduous stands. Thus, birch as a quick-growing tree species will reach the necessary dimension of the required assortment faster than coniferous trees. The way how to increase the proportion of young pine stands is even more complicated problem, which the LVM intends to solve by planting pines in felling areas of the appropriate forest types.
Dry Site Forests Prevail
Forest management in a final felling is regulated by the Law on Forests and Cabinet Regulations on tree felling on woodland that are binding upon every person who manages forest. These documents are based on the growth conditions of a stand that are characterised by forest types and the site indices that are closely related to the former. According to types of growth conditions forests fall into five groups.
Forests on natural sites:
- dry sites
- wet mineral soils
- wet peaty soils
- Forests on drained soils:
- drained mineral soils (peat-layer < 20 cm)
- drained peaty soils (peat-layer > 20 cm)
Dry sites prevail in the forests managed by the LVM, in such a way making the basis of the LVM activities. These forests are characterised by good ground and wind resistance, and forest management practices and tending performed in these forests are the most effective.
Wet mineral soils take up 12%, wet peaty soils 11% of the total forest area. A great deal of biological diversity of Latvia’s forests is found in these forests. Drained forests (forests on drained mineral soils and drained peaty soils) occupy 22% of the LVM area. The productivity of these forests has increased 2 to 2.5 times in comparison with the forests on excessively wet mineral and peaty soils before drainage.
Productivity of Forest Stands is Characterised by Standing Volume
The productivity of forest stands is characterised by standing volume that can be acquired as a result of well-considered forest management per hectare in the stands that have reached the felling age. In all felling sites sold by the LVM average standing volume substantially exceeds 200 m³/ha, in the felling sites of aspen that unfortunately due to rot cannot provide a qualitative assortment the volume is even 300 m³/ha.
In order to increase standing volume in the future the LVM plans to increase tending of young stands with the purpose of establishing composition of tree species suitable for the growth conditions and selection of ‘future trees’. The LVM has developed strict quality requirements for major forestry operations including thinning. The requirements are binding both upon the LVM and its co-operation partners.
Volume of Felling does not Exceed Increment
To ensure sustainable utilisation and exclude depletion of the forest the annual volume of felling must not exceed the annual increment of standing volume. The estimated annual increment in Latvia’s forests is as follows: in pine stands — 5.2 m³/ha, spruce — 7.8 m³/ha, birch — 6.1 m³/ha, common alder — 6.2 m³/ha, grey alder — 5.2 m³/ha, aspen — 7.7 m³/ha, oak — 4.3 m³/ha and ash — 8.9 m³/ha. Total annual increment of standing volume in the LVM forests is 7.04 million m³. The largest amount of wood is produced in pine stands (2.99 million m³), in spruce stands (2.02 million m³) and in birch stands (1.55 million m³).
Compare. In the time period from 2000 to 2002 annual sale of wood for cutting in the LVM was 3.8 million m³, 3.08 million m³ of which came from final felling while 0.72 million m³ — from thinning. Thus, the volume of felling equals only 54% of the annual increment of standing volume. Our task is to seize every opportunity to increase the benefit that we can derive from forest resources in the future.
Forest Inventory — Basis for Planning
Information acquired in the forest inventory is the ground on which the forest management planning can be based. The amount of inventory completed in state-owned forests by 2000 was approximately 100 thousand hectares per year. In such a situation information on forest inventory regarding the area of more than 0.5 million hectares was outdated and, consequently, also inaccurate. When starting its operation the LVM rapidly increased the annual amount of the inventoried forest areas. The company’s scheme is to complete inventory in all the territory it manages by the year 2006, thus providing both for inventory data of forest stands and for digital cartographic material that plays a significant role in the overall improvement of the LVM activities.
Since the LVM started its activities forest inventory has been completed in Southern Kurzeme, Central Daugava, Northern Latgale and Southern Latgale forestries. Inventory in Zemgale and Western Vidzeme forestries was started in 2002 and will be completed in 2003.