RNGR.net is sponsored by the USDA Forest Service and Southern Regional Extension Forestry and is a colloborative effort between these two agencies.

U.S. Department of Agriculture USDA Forest Service Southern Regional Extension Forestry Southern Regional Extension Forestry

Flowering of Jack Pine Seedlings Two Years After Application of GA 4/7

Jack pine ( Pinus banksiana Lamb.) seeds were sown in the winter of 1978-1979. The seedlings were transplanted to a nursery in the spring and summer of 1979 and were sprayed biweekly with the gibberellin mixture GA 4/7 or GA4/7 + naphthalene acetic acid. In 1980 ovulate strobili production increased fourfold. GA4/7 was not applied in 1980. In 1981 the controls flowered better than the GA treatments, indicating there was probably no positive carryover or residual effect. Trees that flowered in both years produced more strobili in their second year (1981) than those that flowered for the first time in 1981. Additional keywords : Pinus banksiana , carryover effect, gibberellins, ovulate strobili.


Download this file:

PDF document Download this file — PDF document, 266Kb

Details

Author(s): Robert A. Cecich

Publication: Tree Improvement and Genetics - North Central Tree Improvement Conference - 1981