Bulk method of hardwood cutting propagation ofLarix olgensis

Larix olgensis is a major reforestation species in areas of the northeast part of China. Rooted cutting for vegetative propagation on this Larch has been carried out since 1990, and later the bulk method of hardwood cutting propagation also has been studied. The result is as follows: (1) Cuttings from physiologically juvenile trees are easy to root, and develop better roots. In addition, there are many methods to enhance the cuttings rooting. (2) The good time for seedling transplanting is in the middle of August. Treatments with plant hormones and rare-earth compounds can improve the seedling survival rate, and the survival rate of the seedlings soaked in chelate rare-earth molybdenum compound (300×10⁻⁶) for 3 hours reached 94.00%, 19.49% higher than that of the control. (3) Methods of maintaining juvenility such as hedging, is essential to further developments for operational planting of vegetative propagates. Hedges in 5 years old can produce 91.75 shoots per tree, exceeding the control to 152.2%. (Responsible Editor: Zhu Hong)