Game Management

XII. CONTROL OF COVER [Includes Image Plates]

CHAPTER XII CONTROL OF COVER Definitions. "Cover" and "covert" both mean vegetative or other shelter for game. Strictly speaking, cover is the kind of materials of which the covert is composed. Cover may refer to a single plant or a very small area; covert is a geographic unit of cover. Plant Successions. Control of vegetation for game cover or food must be based on a thorough understanding of the fact that the kind of vegetation on any piece of land does not remain unchanged from year to year if left to itself. Every acre of soil has a definite sequence of vegetative coverings, and unless accidentally or deliberately interfered with, the type of covering now found will be crowded out by the type next in sequence, and it in turn by the next, until the final or "climax" type is reached. It alone is stable when left alone. This sequence of changes is called the plant succession. Each combination of soil, climate, and animal life has its own series of vegetative types. A single step in the succession may take a month, or a year, or ten centuries, but its completion is as inexorable as time itself. The kinds and rates of change vary greatly with soils and climate, and with the kind and degree of interference. In general, the sequence on lands managed for upland game is: I. Bare ground. 2. Weeds. 3. Grass. 4. Brush. 5. Timber. Severe interference, such as clearing and cultivation, throws the succession from 5 back to I. Less severe interference, such as logging, throws 5 back to 4, but if grazing or fire is added, back to 3, or if overgrazing is added, back to 2. The rate of reo turn depends on the continuance of the interference. ;04 CONTROL OF COVER Within each of these five classes, there may be a succession of various kinds or combinations of weeds, grass, brush, or timber. This elementary exposition will suffice to show that control of game cover or food is largely a matter of understanding and controlling the plant succession. So is agriculture, forestry, and range management. Hence the importance of co-ordinating their needs and processes with those of game. A majority of game species are associated with an interspersion of the early and intermediate stages of plant succession (see Chapter V). Cover control deals with maintaining a balance or optimum combination of stages. Stoddard (p. 381) thus sums up this conception of balance for bobwhite: "Food and cover are of equal importance to the covey range, and one is of little use without the other. Farms so intensively cultivated and pastured that there is no cover can have no quail; while cover, be it ever so attractive, without suitable food, will be equally barren of birds." Methods of Cover Control. Cover (and often food) can be controlled by either speeding up or setting back the plant succession . The" tools" used are usually: FOR SPEEDING UP THE SUCCESSION Planting Protecting against fire Fencing against stock FOR SETTING BACK THE SUCCESSION Plowing Burning Grazing Cutting These may all be called" natural" tools. It is also possible to build cover artificially by the use of physical objects (brush, wire or lumber), or by changing the quality of the site through fertilization, drainage, or impounding water, and thus changing its plant succession. These may be called artificial tools. The following captions will set forth the known principles not already explained in Chapter V, and describe practical examples of cover control by some commonly available tools. The game manager may find these suggestive, but he must usually exercise his own ingenuity in devising measures adapted to particular local conditions. 306 GAME MANAGEMENT Cover Functions, ~uality, and Location. Places to feed, hide, rest, sleep, play, and raise young have been specified as the constituent parts of a habitable range. These generalized categories are really too simple to fit the facts. The game manager working in a particular area needs a very detailed" bill of specifications" as to what constitutes such places, for the species with which he is dealing, at each season oj the year. He should also know the degree of variation in the composition and interspersion of cover types which his species will tolerate (see Chapter V). For species on which there is no competent monograph, such as Stoddard's on the bobwhite, the manager will have to devise his own specifications . Even if...