Double-planting can affect gains from weed control treatments

Abstract

Double-planting is the practice of planting two seedlings at every planting spot. When both seedlings survive, then either the less vigorous seedling is removed or each seedling is given an equal chance of being removed. Some researchers double-plant so that tree growth among experimental plots is not affected by initial differences in stocking. However, double-planting might have an effect on conclusions when the response variable is affected by initial survival. A growth and yield program was used to estimate the effects of double-planting on yields obtained from eliminating hardwood competition. As expected, increasing stocking (by double-planting) increased standing volume at age 25 year. If the herbicide treatment increased survival, the predicted increase was greater for double-planting than for single-planting. However, when the use of herbicides reduced seedling survival, the predicted increase in volume gains was greater for single-planted stands.

Parent Publication

• Proceedings of the 14th biennial southern silvicultural research conference

Citation

South, David B. 2010. Double-planting can affect gains from weed control treatments. In: Stanturf, John A., ed. 2010. Proceedings of the 14th biennial southern silvicultural research conference. Gen. Tech. Rep. SRS–121. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 91-94.