2 BULLETIN 1299, U. S. DEPARTMENT OF AGRICULTURE 
are possible: (1) To test as many wheats as are obtainable with the 
hope of finding varieties naturally resistant to bunt and (2) to use 
as parents such resistant varieties as may be found and so to develop 
by hybridization commercially desirable smut-resistant varieties. 
This bulletin deals with the first phase of these investigations, 
namely, a study of a large number of varieties and selections of wheat 
with reference to their relative resistance to the bunt fungus which 
causes the principal losses west of the Rocky Mountains. 
Acknowledgments are due Dr. George M. Reed, formerly Patholo- 
gist in Charge of Cereal-Smut Investigations, Office of Cereal Investi- 
gations, for general supervision of the experiments during 1919 and 
1920. The writers are indebted to J. Allen Clark, Agronomist in 
Charge of Western Wheat Investigations, and V. H. Floreli, Agron- 
omist, Office of Cereal Investigations, and to agronomists of the 
agricultural experiment stations of California, Oregon, Washington, 
and Kansas for furnishing seed for these studies, and to J. C. 13ell, 
Assistant Pathologist, Office of Cereal Investigations, for assistance 
in the experiments at Moro, Oreg. 
The experiments, the results of which are reported herein, were 
conducted in cooperation with the State agricultural experiment 
stations of California, Oregon, and Washington. The investigation 
was planned and conducted by the following persons at their respec- 
tive stations: 
California. — Fred N. Briggs, Assistant Pathologist, Office of Cereal Investiga- 
tions, and W. W. Mackie, Cerealist, California Agricultural Experiment Station, 
Berkeley, Calif,, and Collaborator, Office of Cereal Investigations, Bureau of 
Plant Industry. 
Oregon. — H. M. Woolman, Field Assistant in Plant Pathology, Office of Cereal 
Investigations, and D. E. Stephens, Agronomist and Superintendent, Sherman 
County Branch Station, Moro, Oreg., Office of Cereal Investigations. 
Washington. — E. F. Gaines, Cerealist, Washington Agricultural Experiment 
Station, and Agent, Office of Cereal Investigations, and F. J. Stevenson, Agent, 
Office of Cereal Investigations. 
W. H. Tisdale, Pathologist in Charge of Cereal-Smut Investiga- 
tions, and J. H. Martin, Agronomist, Western Wheat Investiga- 
tions, Office of Cereal Investigations, Bureau of Plant Industry, 
have been responsible for the final preparation of these data for 
publication. 
PREVIOUS INVESTIGATIONS 
Other investigators have studied the relative bunt resistance of a 
limited number of wheats during the past two decades. 
Farrer (4) 1 reported the results obtained by him in 1900 from 
inoculating 10 varieties of wheat with spores of the bunt organism, 
the infection of different varieties ranging from 12 to 95 per cent. 
Additional results were reported by Farrer in 1904 (5). In 1901 he 
developed through hybridization two varieties of wheat, Florence 
and Genoa, which, according to Sutton (10), possessed a high resist- 
ance to bunt. 
Tubeuf (11), working in Germany, in 1901 and 1902 studied the 
relative resistance of 23 varieties of wheat to bunt. None of them 
were totally resistant, but he found a wide range of difference in 
the degree of their resistance. The Ohio and Ontario varieties 
i Numbers in italics in parentheses refer to "Literature cited," at the end of this bulletin. 
