384 PASTURE MANAGEMENT AND LIVESTOCK PRODUCTION 



(B) Throughout season. 



(C) Aftermath (late autumn). 

 (2) CHmatic conditions as affecting for- 

 age yield. 



B. Creation of new varieties of forage plants. 



a. Object: To increase yield, palatability, and 

 reproductive quahties by cross-breeding and 

 selection. 



b. Hybridization. 



(i) Best related cultivated and native 



species (crossed). 

 (2) Best native species. 



c. Selection. 



d. Grazing tests to determine practical values. 



(i) Palatability. 



(2) Reproduction under use. 



(3) Longevity. 



C. Causes, trend, and rate of plant succession on 

 range. 



a. Object : Recognition of early stages of over- 

 grazing in different localities and time re- 

 quired to revegetate lands in various stages 

 of depletion. 



b. Factors influencing succession. 



(i) Climate. 



(2) Soil. 



(A) Moisture content and water- 

 holding capacity. 



(B) Humus. 



(C) Soluble salts. 



(D) Micro-organisms, notably ni- 

 trifying species. 



(3) Vegetational transformations due to 

 grazing. 



(A) Successional stages. 



(a) Rate and composition. 



