First, it may decrease the amount of crown closure time by allowing the landowner to thin earlier. Second, the treatment will increase the nutrients in the available forage before thinning, after the first thinning, and throughout the remainder of the rotation. The improved protein and nutrient levels in the available forage, in concert with other components of a QDM program, will increase deer body weights and improve overall condition. Prune the "crop" trees.
Low-density plantations will grow larger limbs, producing lumber products with larger knots. We can overcome this problem by pruning the "crop" trees to minimize the portion of the bole containing knots. The pruning operation can be completed in two separate "lifts," beginning when the trees grow to 25 to 28 feet in total height. In the first lift, select trees should be pruned to eight or nine feet. This will leave a knotty core of around four to seven inches. It will take two to three additional years for pruning scars to heal. The remaining wood added to that core will be "clearwood" with no knots. Only prune the best third or best half of the trees. The remaining non-pruned trees will be removed during the first thinning. Thin early and hard.
Thin the pine plantation to lower the stand density and improve tree diameter growth for the remainder of the rotation. Remove the diseased, crooked, and/or suppressed trees, and leave the crop trees to continue growing. Conventional thinnings in high-density plantations generally occur at 16 to 20 years, leaving a residual basal area a term foresters use to describe the amount of timber in a stand of 70 to 90 square feet per acre. To grow larger diameter trees, thin the plantations earlier, around nine to 13 years. Remove more timber volume, leaving a residual 50 to 70 square feet of basal area per acre. The benefits from this early and heavier thinning will be substantial for your deer herd. It basically leaves one huge, fertilized food plot. On the forestry side of the ledger the result is equally attractive. Individual trees in the plantations will maintain optimum crown ratios (33 to 40 percent) and will be capable of fully utilizing the increased nutrition provided through the fertilization treatments.
The thinning process is critical for optimizing stand value. The thinning should be completed by a quality thinning contractor. The leave trees or crop trees should be marked by a party representing you your consulting forester as opposed to the timber harvester. Prune and fertilize again after thinning.
In this pruning lift, prune up to 18 feet. This will leave a large-diameter clearwood log in every crop tree. Fertilizing again after the thinning will ensure that the added nutrients are available to the crop trees, and the sprouting wildlife forage. To enhance legume growth at this time, you may want to consider increasing the amount of phosphorus fertilizer that is applied. Phosphorus fertilization has been shown to promote native legume growth and should be beneficial when applied to a thinned stand. Manipulate the forage quality.
Once sunlight penetrates the forest floor after the thinning, legumes, annual grasses, vines, and hardwood sprouts will grow. You can further maximize the wildlife value from the new forage by using prescribed fire and/or herbicides. Applications of herbicides such as Arsenal® will kill the low value sweetgums and promote the growth of valuable forage species like blackberry, greenbrier, and honeysuckle. The prescribed fire will impact the species frequency and composition. The impact will vary, depending on the season in which the burn is conducted. Perhaps more importantly, the burning will keep the vegetation within the deer's reach. Harvest all remaining timber and establish a new low-density plantation.
This final harvest may occur around age 22 to 25 years. By then, you will have produced a stand of 14- to 20-inch diameter trees with a log of clear-wood on each tree and more sawtimber and pulpwood above the clear-wood log. Timber harvest values may be in the $3,000 to $6,000 per acre range. By now the crowns will have closed for the last several years and you will need to allow more light to the forest floor for the wildlife plant production. Clear-cutting the timber will allow the maximum exposure of light to the forest floor and will leave the site in good condition to establish the next low-density plantation.
By implementing this timber management regime, you can significantly improve the wildlife habitat quality of pine plantations when compared to management regimes that stress total volume production. An added benefit is the aesthetic value of these managed plantations. The large-diameter, pruned pine plantations with frequently burned understories are beautiful.
"I manage several large tracts of land in middle Georgia where my client's primary management objectives are wildlife and timber combined," said Todd Hunt of Timber Management Inc., a central-Georgia company that uses these progressive timberland management techniques. "They are sold on the thinning, fertilizing, and burning concepts. My clients see more deer in these areas and are harvesting more quality bucks. The results are equally dynamic for timber production. We have lowered our initial planting density from 726 seedlings per acre to 454 seedlings per acre. Simply put, we are growing bigger deer and bigger trees and my clients love it."
Give these techniques a try on your existing pine plantations, or simply establish a new low-density plantation in your next cutover or even in an abandoned field. You will be pleased with the results.
The approach above represents a management regime utilizing many of the new approaches being used in the management of pine plantations. The best management regime for your land will depend on your individual needs, desires, the inherent quality of the land, condition of the pine stands on your land, and timber markets in your local area. As such, we recommend that you solicit the advice of a forestry professional in the development of timber management plans for your property. Furthermore, to help assist landowners in managing timber on their property, we will be developing a series of articles in coming journals that cover timber management in the Southern U.S.
Derek Dougherty received his BS in Forest Resources, Forest Business from The University of Georgia and is president of Dougherty & Dougherty Forestry Services, Inc. in Aberdeen, North Carolina and president of Progressive Timberland Management, Inc. in Macon, Georgia.
Material from the Quality Deer Management Association.
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