Forest Stand Improvement
What and Why
There are many ways to improve a woodlot. Several options and goals that might be considered include wildlife, timber, recreation, watershed protection and multiple use. Which of these you decide to place the most emphasis on will determine how you manage your land. The focus here is on improving your woodlot for increased or better timber production.
Managing a woodlot for timber can sometimes seem tricky and confusing. We tend to treat woodlots as if they and their management are something mystical. Simply stated, a woodlot is like a garden in that it must be weeded and thinned periodically to attain its fullest potential and produce high quality timber in the shortest possible time.
One of the ways to reach this potential is through Forest Stand Improvement (FSI). FSI is not difficult or complicated forestry operation. It can be done by anyone upon the advice and guidance of a forester.
The purpose of FSI is to provide the necessary growing space for potential crop trees. When selecting a crop tree several factors should be considered: species, vigor, form crown, development quality of the stem and spacing. Whenever possible. the best trees of the most valued species are selected as crop trees and adjacent trees are removed in order to favor them.
Where, When and How Will FSI Pay?
Any woodlot, natural or planted, will be stimulated by an improvement cutting. You should begin thinning as early as possible to gain the benefits of repeated thinnings. The best time to start thinning a hardwood stand is when the trees average between four and ten inches in diameter at breast height (four and a half feet above the ground). Trees of this size class, commonly referred to as poles, respond rapidly to thinning. Delayed thinning fails to get the immediate growth response which is a primary objective.
This does not mean that stands of larger size trees, averaging 10 to 12 inches, should not be thinned. Such hardwood stands are, however, approaching commercial timber size. In most cases, thinnings can be sold as firewood or pulp.
For natural stands, the selection system is used. This is the selection of crop trees of better species, quality and form; and thinning around them to provide the necessary growing space for the crown. Large, coarse trees with no present or potential value, referred to as Cull or Wolf trees, should be removed as part of the improvement operation. (However, when wildlife is a consideration, some of these trees should be left uncut to provide shelter and food.)
For plantations, one of several systems may be used.
- The Selection System as described above is sometimes applicable. Access lanes may be made by removing entire rows of trees at intervals, or lanes may be cut across rows maintaining a grade to minimize erosion.
- The Row-Thinning System, as the name implies, accomplishes the thinning only by the removal of entire rows. Most common is the removal of every third row, which frees one side of each remaining row.
- The Row-Selection System is a combination of 1 and 2. Usually every 4th, 5th or 6th row is entirely removed and the intervening rows are thinned selectively.
Before doing anything in these stands of larger trees, you should get technical advice and/or assistance from the local service forester or a cooperating forester Here is where the training and experience of the forester comes to your assistance. He or she can tell you which trees to save or to cut. and why. Remember, when you delay the first thinning. you greatly postpone the day for a profitable harvest.
Fuelwood As a Product of Thinnings
Our woodlots have often been mismanaged, over cut, or neglected. Past cutting practices left our woodlands with an overabundance of crooked, diseased and otherwise previously unsaleable trees. Through the demand for firewood, a market for the sale of these trees may be available.
By removing these diseased, deformed or dying trees, you can increase the growth of the more desirable trees that are needed for lumber and veneer while increasing the worth of your woodlot.
In some high-quality stands, the trees to be removed are as high in quality as the crop trees. Although this may be disturbing, remember that most of the trees you are removing will not live to maturity. At some future time, they will be shaded out and die.
Each of the thinning and improvement methods described has its particular merits. A forester's advice should be sought as to the method most suitable in your case. This decision will be based on the age of the stand and possible markets for the timber.
Privately owned woodlots are an important contributor to our forest products economy. We need to increase the production of high quality timber from all our forests if we are to meet future needs for wood and wood products.
Good timber is valuable. Do yourself and your woodlands a favor and take steps now to improve your tree stand.