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MISCELLANEOUS PUBLICATION 1271, U.S. DEPARTMENT OF AGRICULTURE 



production varied from 51 percent below average 

 to 43 percent above average during the study 

 periods (16). Clipping Festuca plants 3.8 cm. 

 above ground surface at any time of the season 

 reduced herbage production, basal cover, flower 

 stalks, and height. The effects were more detri- 

 mental during periods of rapid growth. Basal 

 area of Festuca plants was reduced about 50 per- 

 cent the year following clipping, even when 

 clipped 50 days following seed ripening. Four 

 years of rest folloAving 4 years of clipping at the 

 milk stage resulted in little or no recovery of 

 basal area. No flower stalks were produced in 

 the first year of rest, but good production was 

 obtained in subsequent years (16). 



Cattle grazed season-long (late May-late Oc- 

 tober) in three fenced units; one was representa- 

 tive of cutover pine type, and two were repre- 

 sentative of grassland types. In both the grass- 

 land and pine types, cattle grazed certain plants 

 and certain areas more consistently than others. 

 This resulted in a very uneven utilization of the 

 range. The pattern of use was similar from year 

 to year. Nearly all of the plant species in the 

 pine type were grazed. However, 12 species sup- 

 plied 95 percent of the forage consumed by cattle. 

 The degree of use of a species was affected by its 

 abundance, distribution, and the seasonal prefer- 

 ence of the cattle. Use of Festuca averaged only 

 32 percent during 1936-46 in the pine type. It 

 was 65 percent in 1945 and 80 percent in 1946. 

 By 1946, grazed areas had fewer, smaller, and 

 less productive Festuca plants than comparable 

 ungrazed plots. 



Gains of yearling heifers continued until early 

 October, with the highest weight gains during 

 the period of rapid Festuca growth (prebloom to 

 maturity). 



Hormay and Talbot (16) concluded that under 

 continuous seasonal grazing, the desirable plants 

 are destroyed by selective grazing. Selective graz- 

 ing cannot be prevented by adjusting the stock- 

 ing rate, but its harmful effects can be reduced 

 by not grazing the range at appropriate inter- 

 vals. The improvement of bunchgrass range de- 

 pends on restoring the vigor of desirable plants 

 so that there can be an abundant reproduction of 

 these plants. To obtain reproduction, it is neces- 

 sary to rest the range from grazing for three spe- 

 cific reasons: (1) To restore plant vigor, (2) 



to insure seed development, and (3) to insure 

 seedling establishment. Based on the informa- 

 tion developed at Burgess Spring, Hormay and 

 Talbot proposed a rest-rotation grazing system 

 with the following steps: (1) Graze all season 

 for maximum livestock production, which may 

 result in a reduction of plant vigor; (2) rest one 

 or two seasons, until plant vigor is restored and 

 there is some accumulation of litter; (3) rest 

 until seed is ripe, then graze remainder of season 

 to trample seed into soil and for maximum live- 

 stock production; and (4) rest one or two seasons, 

 to permit establishment of new plants. The time 

 required for each step depends on the growth re- 

 quirements of the key species of the range. 



The vegetation in the rested units constitutes a 

 forage reserve that can be used in drought years. 

 Range improvements, such as seeding and con- 

 trol of noxious plants, may be scheduled during 

 rest periods. Stocking is based on the utilization 

 of all forage species. Fairly heavy stocking forces 

 greater use of the less palatable forage species 

 and the less accessible grazing areas (16). 



A trial of rest-rotation grazing was initiated on 

 the Harvey Valley allotment of the Lassen Na- 

 tional Forest in 1954 (15). That area has similar 

 soils, vegetation, and climate to Burgess Spring. 

 Good stands of Bromus inermis Leyss, Agropyron 

 desertoi^um (Fisch.) Schult.. and A. inteivnedium 

 (Host) Beauv. were established by seeding and 

 the native grass stands were improved on some 

 areas by controlling the shrubby Artemisia L. sp. 



There was a drought in Harvey Valley in 

 1959-61. The precipitation from July 1. 1960. to 

 June 30, 1961, was 27 cm. or 59 percent of av- 

 erage. Ratliff and Rader (31) concluded that 

 forage production was adequate for normal graz- 

 ing and that the cattle made good gains. How- 

 ever, the stocking in 1961 was 81 percent of the 

 rated capacity. 



Ratliff (30) reported that preferential grazing 

 occurred under rest-rotation grazing at Harvey 

 Valley. He used a combination of fencing, salting, 

 water development, and riding to obtain more 

 even distribution of grazing. 



Ratliff and Reppert (32). summarizing results 

 of the grazing study at Harvey Valley after 13 

 years, concluded that the performance of individ- 

 ual animals was about the same with rest-rota- 

 tion grazing as with season-long grazing. They 



