Manipulating stocking rate and duration of grazing is fundamental to range management. It has been claimed that rotation grazing systems wiil increase stocking capadty of range whiie maintaining or improving anhnal gains, range condition, and forage production. To test these claims, we compared continuous, Qpasture rotationally de&r&, and &paddock short-duration rotation grazing on mixed-grass range near Cheyenne, Wyo. from 1982 through 1987. Grazing pmsures ranged from 19 to 81 steerdays per tonne of forage dry matter produced. Steers were weighed biweekly; forage production, utilization, and botanical composition were estimated by clipping; and basai cover was estimated by inclined point frame. Basal cover of litter and bare ground responded to stocking rate or grazing systems, but basal cover of vegetation was affected only by years. Steer average daily gain decreased as grazing pressure increased (r' = 0.66); systems had no significant effect. The most profitable stocking rate at 1986-87 costs and prices was approximately 60 to 80% above SCS recommendations, but the increase in return was small and range conditions and forage production probably could not be maintained a1 this rate.

to the effects of grazing strategies on frequency and intensity of defoliation. Stocking rates and grazing strategies may alter botanical composition of rangeland vegetation by altering frequency and intensity of defoliation of individual plant species. We used longinterval time-lapse photography to study frequency and intensity of defoliation of western wheatgrass (Pzscopyrum smithii[Rydb.] A. Love) and blue grama (Bouteloucl groeilis [H.B.K.] Lag. ex Steud.) tillers under continuous season-long and time-controlled short-duration rotation grazing by steers at 2 stocking rates. Frequency, intensity, and variability of defoliation of both grasses were similar under both grazing systems. Western wheatgrass tillers were grazed more frequently under heavy than under moderate stocking, and in 1990 more herbage was removed the second time a tiller was grazed under heavy stocking. Blue grama tillers were grazed more frequently under heavy than under moderate stocking in both years under rotation grazing, but only in 1990 under continuous grazing; more herbage was removed under heavy stocking the second time a tiller was grazed. Under heavy and moderate stocking, respectively, 19% and 36% of western wheatgrass tillers and 42% and 54% of blue grama tillers were ungrazed throughout the grazing season. Few western wheatgrass tillers were grazed more than twice, and few blue grama tillers were grazed more than once. Stocking rates have much greater potential than grazing systems for altering frequency and intensity of defoliation and subsequent changes in botanical composition of range plant communities. Results of grazing studies support this conclusion.

Grazing systems and stocking rates are used to influence livestock grazing behavior with the intent of improving livestock and vegetation performance. In 1982, a study was initiated to determine effects of continuous, rotationally deferred, and shortduration rotation grazing and moderate and heavy stocking rates on steer gains, range vegetation, and distance traveled by and activity patterns of steers. Steers were observed from dawn to dark on 12 dates during 1983, 1984, and 1985, and activity recorded every 15 minutes. Eight steers per treatment (system X stocking rate combination) per date were observed in 1983 and 1984, and 10 per treatment in 1985. In 1984 and 1985, map locations of all steers were recorded at the same times as activity, and distance traveled summed from distances between successive map locations. In 1984, activity of 3 steers per treatment was electronically monitored during darkness. Steers grazed approximately 8.6 hr per day during daylight and 1.6 hr during darkness. Steers grazed an average of 8.9 hr/day during daylight under moderate vs 8.1 hr under heavy stocking, but stocking rate interacted with date in 1984 and grazing system in 1985. Steers traveled farther under continuous than under short-duration rotation grazing at both stocking rates in 1984, but only at the high stocking rate in 1985. Steers had to travel farther to water in the continuous pastures, and may have had to cover a greater area in an effort to select a more desirable diet, particularly under heavy stocking. These differences were not reflected in differences in gain among stocking rates or grazing systems.Rotation grazing systems were developed to improve livestock performance and range condition (Sampson 1913, Merrill 1954, Hormay and Talbot 196 1). Short-duration rotation grazing, more popularly called the Savory Grazing Method, claims to permit a doubling in stocking rate without a negative effect on livestock performance and with an improvement in forage production and range condition (Savory 1988). The claims put forth for the Savory Grazing Method have seldom been supported by research (Gammon 1984, Blackburn 1984, Heitschmidt 1986, Hart et al. 1988.Much of the interest in grazing systems has focused on animal performance and range condition, but grazing systems also affect livestock grazing behavior. Behavior is the sum of an animal's reaction to its environment and its physiology, and may ultimately influence performance (Balph and Balph 1986). Pasture size, distance to water, animal density, and length of grazing period influence livestock behavior (Valentine 1947, Arnold and Dudzinski 1978, Ganskopp and Vavra 1987, and can be manipulated through the grazing systems discussed above. Grazing distribution, forage selection (plant parts, specific plants, and sites) and feeding behavior (bites/feeding station, steps between stations, daily distance traveled, and activity patterns) may be influenced by grazing systems and ultimately may impact animal performance and range Authors are former research assistants,