火炬松超级苗造林试验初报

AFFORESTATION TRIAL WITH LOBLOLLY PINE SUPERSEEDLINGS —— A PRELIMINARY REPORT

以苗高为因子，把火炬松１年生和９个月生苗木分４个等级造林，并对其７年的生长量进行分析，结果表明：等级苗间树高的差异显著；Ⅰ级苗和超级苗一直保持优势，其７年生平均单株材积分别比林分平均单株材积大３７．４１％～３１．９３％（Ⅰ级苗）、２２．６１％～２４．１２（超级苗）。选择优越立地、加强林分抚育管理，超级苗的增产效果将更显著；

Seedlings of loblolly pine were graded based on heights at the ages of nine monthes and one year and planted for test. Growth at the age of seven years was analysed. The result showed that there were significant differences in height between grades. Seedlings of Grade Ⅰ and superseedlings had been keeping their superiorities since planting and were 31.9% and 22.6% respectively higher than the average in volume. More gain can be expected from the superseedlings if good site is chosen and tending management is strengthened.