Abstract:

The experimental forests and dementstration forests of five Larches including L.gmelini, L.olgensis, L.principis-rupprechtii, L.sibirica and L.kaempferi have been established in three different locations of the west of Heilongjiang Province. Through eighteen years observation and comparision, results have been obtained: L.principis-rupprechtii is not suitable for introduction and forestation due to its little growth. The timber production of L.olgensis is higher over 100% than L.gmelini and may become main planting tree species. L.kaempferi was for the first time introduced in the semiarid zone of N48°13′ with rainfall about 500 mm, and its growth in this area was better than in Liaoning and Shandong provinces. Average height of the tree is 12.9m, DBH is 14.5cm and the stand volume is higher above 100% and 50%~100% than L.gmelini and L.olgensis, respectively. As the native tree species, L.gmelini has adaptive capacity to resist the locate cold and drought, so it should be used for planting common timber and protection forests. It is necessary to comhine seletion of tree species with that of superior provenance for raising stability and productive capacity of the larch plantation. The authors suggest that it is better to use the seeds tamed under the China's continental climate in the introduction of L.kaempferi.

Key words: Larch, Introduction, Semiarid zone, Adaptability, Productive capacity