Plan Development and Accomplishment
The first thing in developing a management plan is consultation with the land owner to determine what management activities are appropriate. This may reveal multiple goals for the property. These could include timber harvest for income, harvesting firewood for personal consumption, improving wildlife habitat, recreation, or others.
The first task is to access the forest. To perform this assessment, a survey is made using the basic knowledge of the forester and various forestry tools to determine the tree types present, age of the trees, density of trees, volume of timber present, presence of invasive species, amount of tree mortality, and other data that could include signs of wildlife, streams and wetlands present, historic sites, and potential for endangered species.
There are a number of tools available for forest management. One of the tools that can be used is the Biltmore Stick. The Biltmore stick was developed at the Biltmore Estate near Ashville, NC in the 1890s. Gifford Pinchot, future first chief of the US forest service, and Carl A. Schenck were hired to restore 125,000 acres of land around the Biltmore estate to a healthy forest. This was one of the first efforts to use scientific methods of forest management in the United States. This stick looks similar to a yardstick, and is used to quickly get an estimation of the board feet of lumber available from a standing tree. It has scales to measure tree diameter at breast height (DBH), at four and a half feet, and the number of 16 foot logs that could be obtained from tree. This hallmark of forest management provides a fairly quick, and somewhat accurate measurement of the volume of timber and productivity of the forest.
Measurements can be obtained by more accurate methods, including determining the tree diameter using a tape, and the height using a clinometer. A clinometer is an optical instrument that, among other things, indicates height based on a known base length of a triangle and the angle of inclination. Measurement of a large quantity trees by these methods are not practical. Often, the clinometer and diameter tape are used in conjunction with an increment borer to determine how large a tree is and how well it is growing. This “site index” information is employed to gauge site productivity, and to determine if trees in a forest are growing in a healthy, vigorous manner.
Another simple device used to measure basal area in woodland is the wedge prism. Basal area is the cross-sectional area of a tree at breast height, and provides an indication of tree stocking, or how many trees are found in the surrounding area. Foresters often manage a forest by adjusting stocking levels. In simple terms, if there are too many trees, you thin some out, or if there are too few, you take steps to increase the amount of trees present.
These various measurements yield a snapshot of the present condition of the forest. This information is linked with the landowner’s objectives to develop a prescription. Sometimes, the recommendation is to simply let the forest grow or control the invasive plants to halt their spread and develop a more natural forest condition. Sometimes, the forest has too many trees and should be thinned out, removing trees for personal firewood consumption or selling the trees to a logging contractor. When there are too few trees, the forest contains significant over-mature trees, or when significant mortality is present, the goal may be to harvest some of the larger trees to promote the growth of younger individuals in the forest using a “regeneration” harvest.
Regeneration harvests can take on many forms. If a substantial amount of the overstory is removed, it is classified as an even aged harvest. Examples of even aged harvesting are clearcut, seed tree harvests, and shelterwood harvests. Clearcutting removes most of the overstory; this type of cutting is not very common in our region, used mostly when a pine plantation is in a state of severe decline, due to pine bark beetles. With clearcutting, tree regeneration is dependent on the seeds lying dormant in the understory “seed bank” or seedlings are replanted on the site following the cutting. Seed tree harvest retain well distributed seed trees to disperse seed to help ensure adequate regeneration. Seed tree harvests favor trees that have wind dispersed seed, such as maple and tulip poplar. Shelterwoods are similar to the Seed Tree method, but more trees are retained. Shelterwoods are employed when the goal is to promote nut trees such as oak, hickory, and walnut. The goal of “Uneven Aged” management is to maintain a significant amount of the original canopy with the hope that young trees will grow in the openings created during the cutting. Single Tree selection is the most common type of cutting in our area, where individual trees are cut. Group selection removes small groups of trees, which creates a larger opening to promote the germination and growth of young trees in the understory.
This diversity of harvest and other management practices creates various forest outcomes, encouraging various plant communities and the wildlife that inhabit them. The goal of these techniques is to develop the intended outcome based on the objective for the property. The intent of the management plan is to develop long term recommendations; most plans have a 15 year lifespan. Over the course of 15 years, a variety of practices may be necessary, depending on the circumstances. Help and knowledge to accomplish this is available from a number of sources. One way to start is to consult with a DNR Forester.
Article by Claude Eans, FCFCDB member
Nature note for 8/12/2018