640 



IMPROVING AND MAINTAINING GROUSE COVERTS 



are ideal for grouse and others that are not. Li the latter case the difficulty can usually be 

 ascribed to poor composition, to an over-dense cover, or to the size, shape or general arrange- 

 ment of the ty|)es. The cure involves changing the cover. To accomplish this, any one or a 

 combination of five methods may be utilized. They are cutting, girdling, poisoning, grazing 

 and fire. 



Cutting 



The usual method of harvesting timber products or of eliminating unwanted trees, is to 

 cut them. \^1here grouse cover improvement can be dovetailed with forest operations, this 

 practice should be followed because of the necessity of salvaging the timber which is left 

 uncut in applying any of the other methods. Cutting is the most expensive, as well as the most 

 certain, of all the possibilities here suggested. However, that many hardwood stumps sprout, 

 following the cutting of the tree, is often a drawback especially in maintenance work. 



Girdling 



With species that sprout, girdling ofttimes provides a useful process for checking sucker 

 growth. Care must be exercised to thoroughly separate the bark by a wide cut. Individual 

 trees often take several years to die even though well girdled. In both this and the next 

 method, the trees are left standing, thus providing a likely source of future difficulty. 



Poisoning 



Developed some years ago, this practice has been given extensive trials in improving 

 cover on New York game management areas. The idea is to make a wide band of cuts through 

 the bark overlapping each other and encircling the trunk. Into tliese is injected a poison that 

 will kill the tree or shrub and inhibit subsequent sprouting. 



Sodium chlorate, sodium arsenite, heavy diesel oil, and other plant poisons developed for 

 control work at Cornell University and by the U. S. Forest Service, are used. Though, in 

 the earlier tests, the cuts were made with an axe, it proved more convenient to adopt a poi- 

 soning tool made of hollow pipe, capped at one end and ground to a cutting edge at the 

 other. The liquid is placed within the pipe and, through a valve at the lower end, is fed to 

 the cutting edge each time the tool is vigorously jabbed into the bark of the tree to be killed. 

 The poison is allowed to run into the wound thus formed, thereby putting it in direct contact 

 with the cambium layer which carries the sap. 



Sodium arsenite was found to be the most effective of the poisons tested. Its major advan- 

 tage lies in its comparative cheapness and its tendency to inhibit sprouting to a greater degree 

 than does girdling. The success of the treatment depends upon the time of year, the species, 

 and the relative vigor of the individual tree. The following table indicates the degree of 

 susceptibility of the species tested. 



}AJi^m 



TABLE 95. RFiLATINli SU.SCEPTIRITJTY OF VARIOUS TREES 

 AND SHHUHS 1() I'OISOMNCi WITH 

 SODIUM ARSENITE 



