PLANT MORPHOGENESIS FOR SCIENTIFIC MANAGEMENT OF RANGE RESOURCES 



147 



several years to have enough range improvement 

 to justify an increase in stocking. 



When a rotation scheme is initiated, range im- 

 provements such as seeding, brush control, fenc- 

 ing, and water developments are often not prop- 

 erly credited for observed differences when com- 

 pared to unimproved ranges. Rather, there is a 

 tendency to credit the rotation scheme for ob- 

 served improvements in range condition or ani- 

 mal performance. Any improvement that aids 

 livestock distribution will result in greater pro- 

 ductivity. The entire management plan, includ- 

 ing both range improvements and grazing scheme, 

 is the important consideration. All of the bene- 

 ficial, economical practices should be integrated 

 into the overall management plan. 



Most grazing studies have been established at a 

 fixed stocking rate. Downward adjustments in 

 livestock numbers were made only in severe 

 droughts. A fluctuating forage crop was given 

 little thought in establishing grazing studies. This 

 is probably another reason why many of the graz- 

 ing studies have failed to show much improve- 

 ment in range condition. When ranch operators 

 adopt a grazing system other than continuous 

 grazing, they often allow for a flexibility in time 

 of grazing and deferral, and the number of live- 

 stock grazed. This flexibility may be the differ- 

 ence between success or failure of the grazing 

 scheme. 



A grazing system must be highly flexible. Plant 

 and animal requirements must be considered. For 

 example, some of the range units in a ranch oper- 

 ation may be manipulated to furnish highly nu- 

 tritious forage during the time of the year when 

 livestock need a higher plane of nutrition. This 

 may be done at a sacrifice of some of the highly 

 desirable range species on those units. Further- 

 more, it should be recognized that the critical 

 growth stage of plants varies from year to year 

 because of weather conditions. Due to grazing 

 history and weather conditions, it may be more 

 important to defer grazing in some years than 

 in others. 



Grazing systems should also be tailored to fit 

 a variety of vegetation types, soil types, and herd 

 management plans. This means that there may be 

 considerable variation in specific details from one 

 ranch operation to the next. In some areas, con- 

 tinuous grazing may be the most profitable sys- 



tem. It may be desirable to use a certain grazing 

 system to attain a certain measure of improve- 

 ment and then change to a different system. 



Much has been learned about grazing manage- 

 ment. However, much needs to be done to develop 

 and adapt the most productive grazing scheme to 

 each range operation. In many grazing studies, 

 the major emphasis has been centered on a few 

 species. The value of all plants growing on an 

 area must be considered. Even minor amounts of 

 a few species may contribute much to animal per- 

 formance for a brief, but critical, part <5f the 

 year. Few studies have given attention to forbs 

 and shrubs. Grazing research should include 

 studies on the effects on the entire ecocystem, not 

 just the effects on the livestock and a few of the 

 major plant species. 



Literature Cited 



(1) Aldous, A. E. 



1938. MANAGEMENT OF KANSAS BLUESTEM PASTURES. 



J. Amer. Snc. Agron. 30: 244-253. 



(2) Bentley, J. R.. and M. W. Talbot 



1951. EFFICIENT USE OF ANNUAL PLANTS ON CATTLE 

 RANGES IN THE CALIFORNIA FOOTHILLS. U.S. 



Dept. Agr. Cir. 870. 52 pp. 



(3) Buffington, L. C, and C. H. Herbel. 



1965. VEGETATION CHANGES ON A SEMIDESERT GRASS- 

 LAND range from 1858 to 1963. Ecol. Monog. 

 35: 139-164 



(4) Crider, F. J. 



1955. ROOT-GROWTH STOPPAGE RESULTING FROM DE- 



foliation of grass. U.S. Dept. Agri. Tech. 

 Bull. 1102. 23 pp. 



(5) Duncan, D. A., and H. F. Heady. 



1969. GRAZING SYSTEMS IN THE CALIFORNIA ANNUAL 



type. Abstr. 22d Ann. Mtg., Amer. Soc. Range 

 Mangt, pp. 23-24. 



(6) Fisher, C E., and P. T. Marion. 



1951. CONTINUOUS AND ROTATION GRAZING ON BUFFALO 



and tobosa grassland. J. Range Mangt. 4 : 

 48-51. 



(7) Gartner, F. R., J. K. Lewis, and W. R. Trevillyan. 



1965. EFFECT OF LEVEL OF WINTER FEEDING AND SUM- 

 MER GRAZING IN PRODUCTION OF RANGE SHEEP 

 IN WESTERN SOUTH DAKOTA, 1952-59. S. Dak. 



Agr. Expt. Sta. Cir. 171, pp. 9-20. 



(8) Harris, R. W. 



1954. FLUCTUATIONS IN FORAGE UTILIZATION ON PON- 

 DEROSA PINE RANGES IN EASTERN OREGON. .1. 



Range Mangt. 7 : 250-255. 



(9) Heady, H. F. 



1956. CHANGES IN A CALIFORNIA ANNUAL PLANT 

 COMMUNITY INDUCED BY MANIPULATION OF NAT- 

 URAL mulch. Ecol. 37: 798-812. 



