| Summary: | In the beginning of the 19th century the woodlands in Iceland had degraded to high extent. The main causes were livestock grazing in conjunction with highly erodible volcanic soils and harsh climate combined with big need for fuel wood. The Icelandic reforestation efforts reached an all time high in 1990-2000 when the state started to give economic assistance to different forestry projects. At that time different species and proveniences of trees had been collected and tested at The Icelandic Forest Research, which started its activity 1967, to find an applicable material for forestry planting in Iceland. In the year 2001 planting projects had started in all parts of the country. The main objects of these projects were timber production and/or soil protection depending on local conditions. As the planting work increased in the country, problems with seedling death due to frostheaving became more and more worrying. Several properties of Icelandic soils make them particularily prone to frost heaving. These properties together with climatic factors do that frost-heaving is a big problem in Icelandic forest plantations. When the different frostheaving factors interact all seedlings can be affected. Frost-heaving can go on for many years resulting in poor growth and or seedling death. Climatic factors and the properties of the soils are the main causes for the frost-heaving in Icelandic forestry plantings. Information about these two environmental factors can give an idea about where frost-heaving can be expected. By using different methods through the process from choosing planting material to the planting procedure itself, the risk for frostheaving can be reduced. In a series of field experiments in Iceland 1995-1998 different methods for reducing frostheaving were studied. Use of fertilizer and or of oat-seed of proper amount at the time of planting seemed to work well as methods in reducing the effects of frost-heaving. Methods for same purpose have also been studied in northern Sweden. In one experiment the ...
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