Nov. i6. 1914 Revegetatioji of Range Lands 115 



1. The flower stalks of the important grazing plants begin to appear 

 about July 5 and are for the most part produced between that date and 

 August ID. The more vngorous plants send up their flower stalks first. 

 Plants weakened by annual close and early grazing do not produce 

 flower stalks until late in the season, and then send up only a few. 



2. The seeds begin to mature by August 15, and by September i the 

 major part of the seed crop is ripened and disseminated. Plants weak- 

 ened by close and early grazing do not mature seed unless the growing 

 season is unusually long and exceptionally favorable. 



3. The viability of the seed of most species is low. The germinative 

 power varies with difi^erent species, but especially with the vigor of the 

 plants. Those which make a weak vegetative growth produce seed of 

 very low viability. 



4. The seeds of the most valuable species lack means for working 

 themselves into the ground, and, if reproduction is to be secured, they 

 must be artificially covered. 



5. In the Hudsonian zone the germination period begins about June 

 25, and growth begins generally by July 15. 



6. During the first year of growth, a period of about 10 weeks, the 

 forage seedlings make a vigorous development. Owing to the friability 

 of the surface soil, however, and the superficial position of the roots at that 

 time, there is rather a heavy loss of seedlings from freezing and drought 

 during the spring period. 



7. During the donnant periods there is virtually no loss of seedlings. 

 The only factor causing loss is erosion. 



8. In the second and subsequent seasons physical conditions are favor- 

 able to rapid development and growth of the young plants. By the 

 end of the third season viable seed is produced. 



DIFFERENT GRAZING SYSTEMS IN THEIR RELATION TO GROWTH 

 REQUIREMENTS AND REVEGETATION 



From the facts brought out by the life-history studies it is plain that 

 a rational method of grazing should (i) avoid weakening the vegetation 

 through continuous grazing prior to seed maturity; (2) utilize, so far as 

 practicable, the trampling of the animals in planting the seed; and (3) 

 provide for protecting the reproduction against heavy grazing until it 

 is firmly established. 



At the present time grazing on the National Forests is carried out 

 under one of three more or less distinct systems: (i) Yearlong or season- 

 long grazing year after year; (2) yearlong or season-long grazing com- 

 bined with an occasional total restriction of stock during the entire year 

 for the purpose of giving the forage plants a chance to reproduce; and (3) 

 deferred grazing, which aims at a rotation in the time of using each por- 

 tion of the range, each year allowing an area to reach seed maturity 



