Skógræktarritið - 15.05.2001, Side 86

Skógræktarritið - 15.05.2001, Side 86
creased dramatically during tha last decade, the main rationalle being rural development aid and carbon sequestration. Because of this, planting has increased to about 5 million seedlings annu- ally and is set to continue to increase during the next decade. At the same time, increased consideration of environmental issues has led to changes in both afforestation planning and implementation. Exotics are no longer planted into birchwoods, wetlands are not drained for forestry, species mixtures are now planted instead of monocul- tures and in 1999, the native downey birch was the most planted tree species in lceland for the first time since 1951. The major tree species used in lceland Downy birch (Betula pubescens Ehrh.) and its hybrid complex with Betula nana (L.) This is the only native species that forms continuous forests or woodland. The total area of birchwoods is about 120,000 ha, of which 20,000 ha are birch forests taller than 5 m, reaching a maximun height of 12-13m, and 100,000 ha are scrub. This amounts to about 1.2% of the land area of lceland, compared to an estimated 25-30% (basical- ly the entire lowland area) forest and woodland cover at the time of settlement in the late 9th cen- turyAD. Most of the birch scrub is a hybrid complex between Betula pubescens and B. nana. Most of the birch in S- and W-Iceland is very low-growing, whereas true forests can be found in N- and E-Iceland. The birch woodlands were an essential resource to the Ice- landic people for 1000 years; being utilised for fuel, charcoal (for iron smelting and tool mak- ing), building material and fod- der for cattle and sheep. The demise of forests was the main cause of both general poverty and the incredible soil erosion that has taken place. The birchwoods are no longer economically important but their preceived importance as habitat, for soil protection and for recre- ation and landscape is increas- ing. Planting of native birch has been increasing in recent years, comprising 37% of the total planted in 1999 or 1.2 million seedlings. Atotal of 14.7 million downy birch seedlings were planted in lceland between 1945 and 1998, making it the second Icelandic downy birch at Hallorms- staður. Height 11-12 m. (Photo: T. Eysteinsson) most planted species, after larch. Efforts are under way to improve native birch through selection and breeding. Russian (Larix suíiaczewii Dylis) and Siberian larch (L. sibirica Ledeb.) Taxonomists disagree as to whether these are one or two species. Their destinction is how- ever useful for Icelandic forestry. Siberian larch from southern Siberia and the Altai mountains was most planted earlier, but 84 SKÓGRÆKTARRITIÐ .2001 l.tbl.
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