Timber—A Modern Crop

by R. R. REYNOLDS

TIMBER can be as much an annual farm crop as corn, cotton, or potatoes. Stands of trees are easier to establish than some other farm crops. In reasonably well-stocked and managed stands the production of cellulose to the acre is much greater than that of cotton. And, contrary to the opinion generally held, the crop can be harvested on an annual basis. It is the only one that can be harvested at the convenience of the owner. It can provide profitable off-season employment in winter.

How much timber and value will a farm woodland yield? How much time must a farmer spend in managing and harvesting the timber crop? How does he establish, then manage and tend,- and finally harvest the tree crop? These problems and many more are being answered by Forest Service foresters on the Crossett Experimental Forest in Arkansas.

The forest, located in the shortleaf-loblolly pine-hardwood belt of southeastern Arkansas, contains some 1,680 acres of typical second-growth stands. It was given the Government by the Crossett Lumber Co. in 1937 as a timber research center. Most of the area had always been in timber, but some places, which now contain old field stands of pine of Pulpwood and sawlog sizes, grew corn and cotton 35 to 60 years ago.

The virgin timber, 12 inches in diameter and larger at the stump, was Cut in 1915 and 1916. Since the lumber companies at that time had no thought of growing timber and no idea of ever coming back for a second cut of forest products, no effort was made to care for the young trees in the stands, and, consequently, many were broken or badly injured in the logging. Furthermore, many of the remaining trees were killed by the fires that burned over the area frequently between 1915 and 1934.
The stands present in 1937 varied considerably. A few were well stocked, with volumes running up to 8,000 feet of sawlogs to the acre. Others had less than 1,000 feet an acre. All stands contained large numbers of defective and limby low-grade hardwoods that occupied nearly half of the effective growing space. Because of the repeated fires, some spots had no trees of any kind. Others that had escaped fire bore dense stands in which the trees were growing very little because of overcrowding.

Such conditions are typical of a large part of the farm woodland and the timberland of the larger lumber, pulp, and other wood-using industries in the region. They are a challenge to workers in forest research to find the methods and means of rehabilitation.

The first step in this program of rehabilitation of the Crossett Experimental Forest was complete protection from uncontrolled fires. Where pine seed trees were present, this protection resulted in a dense stand of pine seedlings in the open spots within 3 years after protection was started. Nine years later many of these seedling stands were nearly of pulpwood size and ready for the first thinning. Additional thinnings will be necessary at short intervals; with proper management these stands will produce a cut of products at intervals of 3 or 5 years for 50 years or more without reseeding or establishing a new crop.

Next, the low-grade hardwoods were cut. The stands were further placed in good growing condition by the removal of the mature, crooked, limby, and defective pine. Where the trees were too thick some of the poorest were removed. Five to 9 years after this improvement cutting, 500 or more valuable pines of pulpwood size grow on many acres where originally stood only low-grade hardwoods. - Furthermore, the reserved larger trees in the whole forest have responded remarkably to the improvement cutting. The growth rate on the small trees has increased by 30 percent and on trees of sawtimber size by nearly 70 percent over what it was before management was started. Where the growth was originally 200 board feet an acre a year, it is now 340, and still is increasing.

A study of the place that forestry should have on the farm was undertaken in 1937. In it, we used a well-stocked but otherwise natural pine-hardwood second-growth stand of 40 acres. The well-stocked area was selected in order to demonstrate returns that could be expected once the volume per acre of the present understocked average farm forest was built up to desirable levels. The present volume of the growing stock and the total amount of growth produced during the year were first determined by an inventory and growth study. Based on this information, a number of the larger or less valuable trees, having a volume equivalent to the volume of growth during the year, were marked for cutting. From these marked trees a volume of firewood equal to the annual requirements of the average farm was produced first. Next, a number of fence posts needed to repair the farm fences were cut. The rest of the marked trees were then cut into one or more cash crops, such as logs, poles, piling; pulpwood, or veneer blocks.