Management of arid western ranges must be based upon the physiology of the individual plants which constitute the range. Too little is known of the ability of range plants to continue normal functioning under stress of grazing. Grazing doubtless has some beneficial influences in arid climates because it reduces transpiring surface. Possibly "pruning" has some stimulating effect, especially upon shrubs, and also, grazing animals plant seeds through trampling action. Despite these possible benefits, both trampling and removal of herbage by grazing must be .regarded as fundamentally detrimental to the welfare of plants, especially in arid climates. Trampling, especially on wet soils during early spring months, is injurious to both mature plants and new seedlings; however, in general, removal of herbage is probably far more injurious. Ability of the individual plant to withstand herbage removal appears to be basically important in range conservation.
Studying effect of grazing by artificial means, such as clipping the herbage with shears, has been criticised, yet it seems the most sound method of studying forage plant physiology, since clipping permits accurate measurement of herbage yield. The experiment reported herein was designed to test the basic response of a single grass species to herbage removal at various seasons as measured by forage production and chemical composition.
Stoddart, L. A., "Bulletin No. 324 - Some Physical and Chemical Responses of Agropyron Spicatum to Herbage Removal at Various Seasons" (1946). UAES Bulletins. Paper 285.