[Chap. V LOCAL PLANT COMMUNITIES 49 



munity by species from neighboring communities. These changes are not 

 due to an alteration in the heredity of the species involved. Changes in 

 heredity, however, must not be overlooked, for they are known to occur 

 at times, as we shall see in later chapters. 



GENERAL REFERENCES 



Bear, F. E. Theory and Practice in the Use of Fertilizers. John Wiley & Sons, 

 Inc. 1929. 



Gustafson, A. F., ef al. Conservation in the United States. Comstock Publish- 

 ing Co., Inc. 1939. 



Scott, John M. Permanent pastures for Florida. Florida Dept. of Agr. Bull. 27. 

 1929. 



Sears, P. B. Deserts on the March. Univ. of Oklahoma Press. 1935. 



Symposium: Erosion prevention capacity of plant cover. Iowa State College 

 Jour, of Science. 9:323-497. 1935. 



U. S. D. A. Yearbook of Agriculture. Soils and Men. 1938. 



U. S. Golf Association Green Section. Bulletins. Washington, D. C. 



Welton, F. A., and V. H. Morris. Composition of grass from woodland and 

 from open pastures. Jour. Amer. Soc. Agron. 18:226-238. 1926. 



SPECIAL READINGS 



Barnes, E. E. Ohio's pasture program. Jour. Amer. Soc. Agron. 23:216-220. 

 1931. 



Cook, I. S. West Virginia pastures. W. Va. Agr. Exper. Station Bull. 177. 1922. 



Morgan, M. F. Lawn fertilization. Conn. Agr. Exper. Station Circidar 77. 1931. 



Schuster, G. L. Pasture improvement. Delaware Agr. Exper. Station Bull. 

 164. 1930. 



Sears, P. B. Deserts on the March. Univ. of Oklahoma Press. 1935. Chap. VHI. 



Tehon, L. R. Rout the weeds! ///. Islat. Hist. "Survey Circular 34. 1939. 



Westover, H. L., and C. R. Enlow. Planting and care of lawns. U. S. D. A. 

 Farmers Btdl. 1677. 1931 (Revised 1935). 



Wiggans, R. G. Studies on various factors influencing the yield and the dura- 

 tion of life of meadow and pasture plants. Cornell Agr. Exper. Station Bull. 

 424. 1923. 



