GRASS AND WATER AND TREES

Chas. A. Connaughton

NEARLY EVERY acre of range has other uses and values besides forage Production to protect watersheds, Produce timber, give wildlife a home, and provide places for recreation.

These are the "other" values of the range. Each is important; on some ranges, indeed, the demands of one or more may dominate or even exclude grazing. If grazing is properly managed, however, the various uses are usually compatible with the use of forage by livestock.

A description of how grazing can be coordinated with watershed and timber management is given here to provide a basis for a fuller understanding of the concept of management for multiple use.

In theory it is not particularly hard to coordinate grazing and watershed use on range land. In the main, it requires simply that methods and systems of grazing be practiced that will insure maximum production of forage so that grazing capacity is maintained and a cover of vegetation is provided to stabilize soil and help regulate runoff. Favorable watershed conditions are thereby insured.

There are exceptions to this general premise : On some steep slopes the loose soil is held in delicate balance by the plant cover, as on parts of the Boise River watershed in Idaho, the Salt River watershed in Arizona, and the South Platte River watershed in Colorado. On these slopes, it is unwise to attempt any grazing because the risk of erosion is too great. On most watersheds, however, properly managed grazing is entirely feasible.

In practice, the coordination of grazing with the watershed service of the land is not so simple. Grazing is often handled in such a way that the plant cover deteriorates and maximum forage production is not maintained; then the watershed values of the range are likely to decline because reductions in plant cover usually cause unfavorable changes in the soil, scarcely perceptible at first but ultimately strikingly evident in accelerated erosion and rapid runoff. These are marks of a damaged watershed.

Picture in your mind a range watershed with which you are familiar. Originally nature combined its soil, plant, and climatic factors in a way that imparted a given set of watershed characteristics, which were determined by the amount and kind of runoff, the movement of soil by wind or water, the quantity of silt in the runoff, and other elements. The natural factors may have created a stable balance. Well-vegetated slopes were yielding a steady flow of silt-flee water, or, at the other extreme, the vegetation may normally have been scant, with considerable normal erosion and rapid runoff. The detailed characteristics are unimportant, however, because the general premises that follow are applicable regardless.

By and by, commercial grazing began on the watershed. If the numbers of domestic livestock were held at a point where the yield of forage was sustained at a maximum through the years, the natural characteristics may have changed little. There may be minor scars of use, such as trails and salt grounds, but, in brief, grazing and watershed use have been coordinated.

More than likely, however, the range with which you are familiar was subject to economic pressures and stocking was increased to the point where the forage was too closely cropped. When this happened, the plants began to lose vigor, and less and less organic material was produced to be returned to the soil. Fertility in turn declined.

The soil became less porous. This process probably started rather slowly without being noticeable in its early stages, but it is a vicious circle the less vegetation produced the poorer the soil conditions, and the poorer the soil the less vegetation produced.

Without adequate plant material in and on the soil, the stage was set for erosion and rapid runoff. There again the effects pyramid, because a small loss of soil by erosion changes the surface by reducing porosity and creates small channels which concentrate runoff. This sets the stage for even greater soil losses and runoff.

Where such watershed deterioration proceeds unchecked and has reached an advanced state, we have the conditions which are all too common today the silt-choked stream channels; flash stream flow with a heavy burden of soil; gullied valleys and meadows with lowered water tables; slopes barren of fertile topsoil; as well as irrigation and other improvements and even lives destroyed by flood and mud flows. Where these conditions prevail, coordination of grazing and watershed values has not been achieved, and to attain it after the damage is done may require drastic corrective measures.

What corrective actions will bring about belated coordination of grazing and watershed values on the range? Every watershed has its own peculiar set of conditions, but the first step is generally obvious. Grazing pressure must be removed or reduced so that the plant cover can restore itself to normal. This means reducing animal numbers or improving management practices and methods, or both. If the soil fertility has not been seriously depleted and perennial plants remain which 'can reproduce themselves, restoration may be accomplished fairly rapidly after grazing is gauged to permit abundant natural seeding or other revegetation.

If soil fertility or the plant cover has been badly depleted, natural recovery may be exceedingly slow even if all livestock is excluded. Where this is the case or where it is desired to hasten natural processes, attention should be given to supplemental measures. Artificial reseeding aids in reestablishing a normal plant cover. Engineering works ( such as check dams and water-holding or water-spreading devices as were used with striking success on the mountain watersheds between Ogden and Salt Lake City, Utah) are means of arresting deterioration and hastening a return to a stabilized condition, especially when supplemented with reseeding. Whether these supplemental measures should be used will be determined by the potentialities of the land itself and the interests and needs of both the landowner and the public.

A further point: Watershed values of an entire range can be seriously damaged if misuse is permitted on localized key areas comprising no more than 5 to 10 percent of the total. Thousands of acres of slopes surrounding a few key meadows may have an excellent plant cover, but if the cover on the meadows only is depleted, erosion there may produce enough silt to make unusable the yield of water from the entire drainage. Or, runoff from these small, misused areas alone may be sufficiently accelerated and concentrated to overtax channel capacities and cause floods and aggravated channel erosion. This point has been demonstrated strikingly in the past when devastating flash floods and mud flows issued from certain canyons of the Wasatch Front in Utah as a result of grazing misuse on localized key areas that make up no more than 10 percent of the total watershed.

The coordination of grazing and watershed values on important range watersheds cannot, therefore, be a piecemeal arrangement. It must be accomplished on practically every acre if it is to be successful. One of the range manager's most important tasks is to hold the necessary scars of use, like trails and salt grounds, to an acceptable minimum, compatible with watershed values. If this cannot be done, watershed values can doubtless be protected only by the exclusion of grazing.