45.北海道北部の泥炭地における前生林の造成法(2) : ドロノキの生長量(会員研究発表講演)

抄録

This experiment has started two years ago. Early October 1966 the new 550 m long mounds were rolled-up with bog-bulldozer and planted with wood-cuttings of poplar and willow, 25 cm distance. The growth is shown in Table 1. A few data about its quick growth (Fig. 3) show that Japan poplar, Populus maximoxviczii, on the mounds will be able to reach 10 m high in ten years and that it can form functional low tree belts early, which nurse proper shelterbelt tree of Todo fir, Abies sachalinensis. Afforestation on peat-bog needs complete weeding, two or three times in the first year. Planting must be practiced immediately after land-preparation, because weeds-chiefly reed, Phragrnites, and other newly invensioned species-recover very quickly and become severe competitors for the plants in spaces above and under the ground. The preparation and planting did not require expensive drainage or soil-improvement: the land use of peat-bog in forestry costs very little, compared with that in agriculture.