By Ray A. Newbold
Journal Correspondent

A landowner meeting November 27, 2007 provided encouragement and guidance for forest landowners whose timber stands may need cultural treatments. Three speakers addressed stocking levels and means to achieving tree spacing that will provide good timber growth while improving forest health and environmental productivity.

McDavid Hughes, a forestry and logging consultant in West Monroe, presented results of a pine plantation thinning study, first thinned at age 15 and re-measured at age 25. Initial planting on a 10'x10' spacing allowed mowing with a rotary mower and small tractor at ages 1, 3, 5, 10, and 15-years. Tree measurements were made at ages 5, 10, 15 (before and after thinning), and at age 25 prior to harvest. At age 15, five thinning prescriptions reduced stand density from 400 trees per acre in unthinned plots to 209 (very light thinning), 174 (light), 139 (medium), 122 (heavy), and 105 (very heavy).

The immediate effect of thinning was an increase in average tree diameter of the remaining trees when the smaller trees were removed. The annual growth was then added to fewer trees resulting in increased diameter growth rates. Ten years after thinning there was a progression of tree diameters beginning at 10.9-inches for the unthinned plots and increasing to 15.4-inches for the 105 trees on the heaviest thinned plots. Harvest products were identified as utility poles, sawlogs, or pulpwood. Tree volumes and dollar values were then calculated on a per-acre basis. The heavily thinned plots returned 28% more value than the unthinned plots at age 25; $184.72 per acre per year at today's prices and harvest costs.

Hughes' recommendations are to plant loblolly pine trees at a row interval that will allow access for competition control and thinning without removing a row of trees. Each tree should have 100-square feet of space, so with a 14-foot row spacing trees would be planted 7-feet apart in the row. A heavy thinning should be made at age 15 and trees to be cut should be marked by a competent forester or technician. Density after thinning should be about 140 trees per acre.

Steve Hotard, Area Forester with the LSU AgCenter, then recapped a thinning study on the Calhoun Research Station that was hit by a heavy ice storm within months after thinning. The stand with wide spacing (12-feet between rows) stood up well while the close spacing was broken down. Photos taken by Dr. John Adams of the School of Forestry at Louisiana Tech show a sharp contrast between the stand which grew under crowded conditions and one which was well spaced.

Wayne Roberts, NRCS Forester, reviewed practices and sign-up information regarding financial assistance available to non-industrial forest landowners through the EQUIP program (Environmental Quality Incentives Program) in the Farm Bill. EQUIP is a voluntary program for farmers and ranchers with the objectives of promoting agriculture production and environmental quality as compatible goals. Funding assistance is available to install or maintain conservation practices that enhance soil, water, and related natural resources while sustaining the production of food and fiber.

Site preparation, tree planting, pre-commercial thinning, pine release, prescribed burning, or conversion of cropland and pastures to forests all may qualify as they contribute to enhanced forest health or wildlife habitat. In addition to the environmental quality goals, these practices, coincidentally, also contribute to the intensive production of forest products. Landowners needing assistance or advice regarding their property should contact their local NRCS Field Office in their Soil and Water Conservation District.

Although market prices fluctuate with seasons and economic conditions, the demand for forest products has not declined. In Louisiana, the timber harvest has remained between 25- and 30-million tons for the last 20 years. Currently the pulpwood market is strong and thinning provides a source of fiber for this important market. The message that is materializing is to plant fewer trees initially than has been recommended in the past, and if your pine plantation is already established, thin at the earliest opportunity. In general, stands reaching 40 feet of tree height will be candidates for a first harvest operation.

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