To Thin or Not To Thin
To Thin or Not To Thin
Wildlife biologists have recognized the value of thinning pine timber stands for wildlife management for a long time. The benefits to wildlife are derived from opening a closed tree canopy to allow sunlight to reach the ground. The sunlight stimulates plant growth and produces an abundance of various food and cover plants valuable to wildlife. When thinning is combined with periodic prescribed burning, wildlife habitat is further improved and sustained.
More specifically relating to quail management, closed canopy stands shade out food and cover and also may serve as "ecological traps" because increased predation within these stands is increased. A good rule of thumb for thinning stands for quail is to thin early and thin often to keep approximately 40-60 percent of the ground in direct sunlight at high noon. In forestry terms this corresponds to a basal area of approximately 40-70 square feet per acre.
Professional foresters also frequently recommend thinning to enhance timber production and management. Thinning benefits trees that are left standing by reducing their competition for available nutrients and stimulating increased tree growth. Additionally, thinning assures that future wood products are of high quality and bring the best prices to landowners. Thinning also provides landowners with an intermediate source of income.
However, when the pulpwood market is depressed, as it has been for the last few years, landowners are faced with the decision whether they should thin their pines when they bring little or no profit. Many landowners delay thinning in hopes that the pulpwood market will rebound and they can realize a profit from their investment. Wildlife is harmed because this delays habitat improvements that would otherwise benefit many species.
But, are landowners actually protecting their investment by not thinning in depressed pulpwood markets? Research conducted by the Center for Forest Business at the University of Georgia Warnell School of Forestry and Natural Resources (UGA) suggests otherwise.
Researchers from UGA compared the percent return on investment for several different timber management schemes. Included in the comparison were management recommendations for no thinning, thinning only, and thinning combined with fertilization. The results clearly showed that thinned stands, even during times of depressed pulpwood prices, brought a higher rate of return throughout the life of the stand than unthinned stands. This is good news for wildlife and an important piece of information for landowners who struggle with the decision to thin during depressed pulpwood markets. So for healthier trees, healthier wildlife, and a healthier return on your timber management investment, remember that thinning is a worthwhile practice for most landowners in almost every scenario.
For complete information on the University of Georgia study see the Spring 2003 edition of Georgia Forestry Magazine published by the Georgia Forestry Commission or visit their website . For more information on the value of timber management for quail & other wildlife visit the Wildlife Resources Division website .
--Mark Whitney, Georgia DNR, Wildlife Resources Division