Sanitation Cuttings

Sanitation cuttings remove trees to prevent or reduce the spread of insects and diseases to the residual stand (Hawley and Smith 1954, Helms 1998, Smith 1986, Society of American Foresters 1989). Simply cutting low-vigor trees from a community does not qualify as sanitation cutting, however. Cuttings must be targeted at trees that are already damaged or those that might serve as good habitat for the spread of a disease or an insect population (Nyland 1996).

Almost all species in the southern Appalachians are susceptible to some injurious agent. Certain conditions can cause trees to become more vulnerable, or likely to die from attack. For example, overstocking, droughts, air pollution, site conditions, and other insects and diseases can increase a trees vulnerability to injurious agents. Hicks (1998) stresses that it is important to take into account the "stress loading" of a given stand and the particular individuals within the stand when making decisions about which trees to favor in a sanitation cutting.

In southern Appalachian stands, sanitation cutting is most applicable to mixed stands containing species that vary in vulnerability to a pest buildup. In planning a sanitation cutting, the forester must be aware of the potential hazards from injurious agents that a particular stand is likely to experience. This knowledge can be gained through "hazard rating" (Hedden 1981, Hicks and others 1987, Hicks 1998).

There are several economic trade-offs with sanitation cuttings. Although they include investments to fell and dispose of unmerchantable trees, failing to invest in this operation may allow a serious insect or disease problem to develop and cause a loss that eventually exceeds the compounded costs of sanitation cutting. Sanitation cutting can be done as a noncommercial venture by poisoning or girdling unmerchantable trees. Generally, landowners must be able to justify the investment based on the value that accrues on the acceptable growing stock favored by the sanitation cutting (Nyland 1996).

Sanitation cuttings provide the most benefits when they can be accomplished in conjunction with thinning or improvement cutting or when a merchantable product can be obtained. For gypsy moth management in fully stocked mixed mesophytic stands with a substantial oak component, Gottschalk (1982) proposed a sanitation "thinning" by selectively removing oaks (the preferred host), especially individuals of lower vigor. This treatment reduces the susceptibility and vulnerability of the residual stand. Some oaks, and better quality individuals of less vulnerable species, can be left. These guidelines would susceptibility by reducing the proportion of preferred host species, reduce vulnerability by leaving more vigorous trees, improve the overall quality of the stand, redirect resources to the residual trees for faster growth, and generate income from the sale of the thinned trees (Hicks 1998).