90 IMPROVEMENT AND MANAGEMENT OF FARM PASTURES 



on seed, are most common in the arid regions. Many culti- 

 vated forms, like orchardgrass, also have this habit of growth. 

 The sod forms spread much more rapidly than do those of the 

 bunch habit of growth. The form of growth is determined by 

 the way the new stems or branches develop. 



In bunchgrasses the root stems, or " tillers," which originate 

 a short distance below the surface of the soil, grow up inside of 

 the leaf sheath (Fig. 25). In sodgrasses the end of the new 

 branch forces its way through the base of the leaf sheath and 

 spreads to varying distances before coming up. At the point 

 where it ascends a number of anchor and feeding roots usually 

 form (Fig. 26). 



In certain humid regions well-established sod pastures are 

 often grazed early and repeatedly year after year without ap- 

 parent damage; but such repeated grazing of a bunchgrass 

 pasture soon causes its destruction. 



The life period of forage plants is not well known. Most 

 perennial grasses in favorable environment are long-lived, but 

 the same species under rigorous conditions may live but a short 

 time. In the Northwest the yield of timothy usually declines 

 sharply after the fifth or sixth year. If, however, a suitable 

 fertilizer is added, timothy may yield satisfactorily for twice 

 that period. A sod cover may endure for a hundred years or 

 more; but, as the stand is continuously renewed by plants origi- 

 nating from the rootstocks or stolons, the entire stand is rejuve- 

 nated from time to time. 



HOW THE FARMER MAY IMPROVE THE PASTURE 



In some countries the real brains of the farm are devoted to 

 pasture management. While a permanent pasture may con- 

 tinue to produce for many years, it is doubtful if any tillage 

 system requires more careful attention or provision than does 

 the continuous production of a highly nutritious, heavy-yielding 

 forage crop. Choice forage should occupy the entire pasture. 

 Land values are now too high for only a portion of the pasture 

 vegetation to be of use as forage. 



Unfortunately, very Httle experimental work has hitherto 



