A PASTURE HANDBOOK 29 



roots and a fair cover of foliage to protect them from injury when 

 their vitality is low and conditions are unfavorable. 



In the humid parts of the United States forests are the climax type 

 of vegetation and trees will dominate over grass if not interfered with 

 by man. In such regions fairly close grazing is helpful in maintaining 

 a grass cover. Trampling as well as grazing by cattle and sheep assists 

 in the production of a good turf. Sheep are believed to be especially 

 beneficial in compacting the soil, and goats help by browsing to prevent 

 brush and trees from occupying grazing lands. In general, reasonably 

 heavy grazing favors plants that require light and that grow best on 

 a compact soil. Most stoloniferous plants hke bluegrass, redtop, 

 bentgrass, and white clover are of tliis type. 



On the other hand, in arid and semiarid country, where grasses are 

 the climax form of vegetation and may even conquer such hardy 

 plants as sagebrush, continuous heavy grazing is destructive rather 

 than helpful. The plants have a short period of growth, on account 

 of the brief rainy spells and the lack of soil moisture during a greater 

 part of the year; thus they cannot perpetuate themselves by seeding 

 or storing plant food in their subterranean parts if they are closely 

 cropped throughout their growing period each year. 



Cattle alone graze more miiformly and will keep a pasture in better 

 condition than horses or sheep alone, but mixed grazing frequently 

 provides a more uniform utilization of the forage. In the case of any 

 class of livestock, the inclusion of some good pasturage and some poor 

 pasturage witliin the same boundary usually results in poor utilization 

 because the stock will overgraze the good pasture and undergraze the 

 poor pasture. Consequently, improving a part of the pasture and 

 neglecting the rest may eventually result in reduced rather than in- 

 creased carrying capacity. 



The bad effects of understocking a pasture may occur when animals 

 are fed heavily with supplemental feeds and do not have to rely much 

 on the pasture for feed. Therefore, they may graze very selectively, 

 avoiding the plants that have become too mature and allowing the 

 less desirable plants to grow and crowd out the more palatable and 

 closely grazed plants. In such cases young stock and breeding ani- 

 mals that are not receiving supplemental feed should follow to clean 

 up what has been left. 



Where grazing is confined to one kind of animals it is likely to affect 

 the quality of the pasture adversely on account of the selectivity of 

 their grazing. Horses are quite likely to graze certain areas very 

 closely and to leave other areas wholly untouched. On the other 

 hand, they may be used to graze down a pasture that has rather com- 

 pletely grown up to coarse herbage. Such rough herbage as they will 

 not eat can be removed by mowing late in the summer. Sheep, too, 

 are much inclined to select the more tender grass and the tender tips 

 of weeds and bushy plants. One of the rules for maintaining a uni- 

 form turf is to graze it all down close at least once a year. In England 

 it has been found that rolling is the most effective means of eradicating 

 moss from old pastures. 



EFFECT OF BURNING PASTURES 



No general statement can be made regarding the advisability of 

 burning over pastures or ranges, except that indiscriminate, uncon- 



