Current issue: 53(4)
Cultivation of ash (Fraxinus exelsior L.), even though it is a native species in Finland, has been hindered by the belief that it cannot produce quality timber in Finland. However, it can be concluded that the quality of ash timber is as good as that of timber imported to the country, if the trees are grown in a fertile site, the crown density is high, and the stand is tended properly. In these conditions, ash wood may have 3 mm ring width or more. Measurements made in ash stands in Turku region and in Åland show that at the best sites ash trees reach a height of 20–22 m in 70–80 years. According to the field tests made by the author, it can be concluded that ash can be successfully grown in Southern Finland in Åland, Turku region, in the coastal areas of Uusimaa and in Karelian isthmus. The species requires a fertile, moist upland forest site. The early growth is best secured by planting the seedlings under a well thinned broadleaved stand, which is then thinned every fifth year. Open lands growing grass should be avoided.
The PDF includes a Finnish and German summary.
The paper describes plant species characteristic for ash (Fraxinus exelsior L.) forests in Denmark, and compares the vegetation to beech (Fagus ssp.) forests, the dominating tree species in Danish forests, which have notably simpler ground vegetation. The writer concludes that ground vegetation can be divided into distinct types. Beech grows in several types of soil differing in their fertility (bonitet). The writer has divided the different soil types by their flora (tilstandstyper). The flora is influenced by three factors: climate, fertility of the soil and soil moisture. The paper defines the types of vegetation which describe fertility of the sites (bonitet), and discusses how age, silvicultural condition and tree species affect the vegetation.
The ash content has been found to correlate with the fertility of peatlands. Relationship between height of 80-year-old stands and ash content of peat in topmost 30 cm layer was examined in Lithuanian conditions. On drained peatlands with ash content of peat from 3% to 8% pine stands increase in height. Ash content of peat being about 7% Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) stands on drained sites are found to be of equal height. Ash content of peat more than 8–9% has no significant effect on growth of pine or spruce stands. Birch (Betula verrucosa (B. Pendula Roth.) and Betula pubescens Erhrh.), stands are less sensitive to ash content of peat compared with other species. Black alder (Alnus glutinosa L. Gaertn.) stands occurred in sites with ash content of peat more than 8–10%. The height of the stands become equal both in drained and undrained sites in the cases where ash content of peat is about 16–18%. Ash (Fraxinus exelsior L.) stands attain high productivity on drained sites with ash content of peat about 20%.
The PDF includes a summary in English.
The aim of the study was to update knowledge of natural range of English oak (Quercus robur L.), European ash (Fraxinus exelsior L.), Norway maple (Acer platanoides L.), small-leaved lime (Tilia cordata Miller), wych elm (Ulmus glabra Mill.) and European white elm (Ulmus laevis Pall.) in Finland, and estimate how far north they could be grown as forest trees or as park trees. The study is based on literature and questionnaires sent to cities and towns, District Forestry Boards, districts of Forest Service, Forestry Management Associations and railway stations.
The northern borders in the natural range of the species succeed one another from south to north as follows: English oak, European ash, Norway maple, wych elm, and small-leaved lime. Occurrence of European white elm is sporadic. The English oak forms forests in the southernmost Finland, while the other species grow only as small stands, groups or solitary trees. According to experiences of planted stands or trees, the northern limits of the species succeed one another from south to north as follows: European ash, English oak, Norway maple, European white elm, wych elm and small-leaved lime. All the species are grown in parks fairly generally up to the district of Kuopio-Vaasa (63 °). The northern limits where the species can be grown as park trees reach considerably further north in the western part of the country than in the east.
The article includes a summary in English.