52 CIRCULAR 491, U. S. DEPARTMENT OF AGRICULTURE 



(42) Lamson, ScRibner F. 



1898. report of the agrostologist. U. S. Dept. Agr., Kept. Sec. 1898: 

 145-152. 

 (43) 



1900. PROGKESS OF ECONOMIC AND SCIENTIFIC AGROSTOLOGY. U. S. Dept. Agr. 



Yearbook 1899: 347-366, illus. 



(44) Lyon, T. L., and Hitchcock, A. S. 



1904. pasture, meadow, and forage props in Nebraska. U. S. Bur. 

 Plant Indus. Bull. 59, 64 pp., illus. 



(45) Nelson, A. L. 



1933. GRASSES, alfalfa, and sweetclover a,t the archer field station. 



Wyo. Agr. Expt. Sta. Bull. 195, 46 pp., illus. 



(46) Nelson, Aven. 



1898. the red desert of Wyoming and its forage resources. U. S. Dept. 

 Agr., Div. Agrostology Bull. 13, 72 pp., illus. 



(47) Nelson, Enoch W. 



1934. the influence of precipitation' and grazing upon black grama 



grass range. U. S. Dept. Agr. Tech. Bull. 409, 32 pp., illus. 



(48) Oliver, George W. 



1910. neav methods of plant breeding. U. S. Bur. Plant Indus. Bull. 

 167, 39 pp., illus. 



(49) Pammel, L. H. 



1897. NOTES ON THE GRASSES AND FORAGE PLANTS OF IOWA, NEBRASKA, AND 



Colorado. U. S. Dept. Agr., Div. Agrostology Bull. 9, 47 pp., 

 illus. 



(50) Parks, H. B. 



1937. valuable plants native to texas. Tex. Agr. Expt. Sta. Bull. 551, 

 173 pp., illus. 



(51) Piper, Charles V. 



1925. cultivated grasses of secondary importance. U. S. Dept. Agr. 

 Farmers' Bull. 1433, 43 pp., illus. (Rev. 1934.) 



(52) Rydberg, P. A., and Shear, C. L. 



1897. A report upon the grasses and forage plants of the rocky moun- 

 tain region. U. S. Dept. Agr., Div. Agrostology Bull. 5, 48 pp., 

 illus. 



(53) Sampson, Arthur W. 



1919. plant succession in relation to range management. U. S. Dept. 



Agr. Bull. 791, 76 pp., illus. 



(54) Sarvis, J. T. 



1920. COMPOSITION AND DENSITY OF THE NATIVE VEGETATION IN THE VICIN- 



ITY OF THE NORTHERN GREAT PLAINS FIELD STATION. JOUT. Agr. 



Research 19: 63-72, illus. 



(55) 



1923. EFFECTS OF DIFFERENT SYSTEMS AND INTENSITIES OF GRAZING UPON 

 THE NATIVE VEGETATION AT THE NORTHERN GREAT PLAINS FIELD 



station. U. S. Dept. Agr. Bull. 1170, 46 pp., illus. 



(56) Savage, D. A. 



1933. BUFFALO GRASS FOR FAIRWAYS IN THE PLAINS STATES. Bull. U. S. 



Golf Assoc, Green Sect. 13 : 144-149. 



1934. METHODS OF REESTABLISHING BUFFALO GRASS ON CULTIVATED LAND IN 



the great plains. U. S. Dept. Agr. Cir. 328, 20 pp., illus. 



(57) 



(58) - 



1937. DROUGHT SURVIVAL OF NATTVE GRASS SPECIES IN THE CENTRAL AND 



southern great plains, 1935. U. S. Dept. Agr. Tech. Bull. 549, 

 55 pp., illus. 



(59) and Jacobson, L. A. 



1935. the killing effect of heat and drought on buffalo grass and 

 blue grama grass at hays, Kansas. Jour. Amer. Soc. Agron. 

 27 : 566-582. 



(60) and Runyon, H. Everett. 



1937. NATURAL REVEGETATTON . OF ABANDONED FARM LAND IN THE CENTRAL 



and southern great plains. Internal!. Grassland Cong., 

 Aberystwyth, Gt. Brit., Rept. Sect. 1. Grassland Ecology, pp. 



178-182. 



