2 BULLETIN 1183, U. S. DEPARTMENT OF AGRICULTURE. 
with this second purpose that this bulletin is principally concerned. 
Careful experiments have been made to determine the compara- 
tive value of varieties within each class of the official grain stand- 
ards for wheat and the relative rank of the varieties in the principal 
quality- factors considered in commercial milling and baking. 
The results obtained furnish a basis for recommending the discon- 
tinuance of the production of varieties of poor quality and increas- 
ing the production of those of good quality. The experiments have 
made possible the early determination of the quality of new varieties 
introduced, or produced by breeding. Several varieties of poor qual- 
ity have not been distributed for commercial growing because of these 
experiments and the production of several other varieties has recently 
been rapidly increased after it was determined that they possessed 
good milling and bread-making qualities. 
The data should be of special value to the milling industry, as the 
inherent qualities of a variety are the basic and. usually the principal 
factors in the milling and baking value of any sample or lot of 
wheat. The effects of season, locality, rainfall, elevation, and soil 
are generally of less importance than varietal differences. The data 
presented in this bulletin, therefore, should be useful to the producer 
in determining the best varieties to grow, and, when identification 
is possible, should be useful to the wheat buyer and miller in select- 
ing and blending wheats to meet particular milling and baking 
requirements. 
General conclusions, based on the milling tests here reported, will 
be found on page 91. 
SOURCES OF THE SAMPLES. 
The milling samples on which the data are based were obtained 
from experiment stations and from commercial sources. In the 
earlier milling and baking experiments conducted by the Depart- 
ment of Agriculture, dating from 1908 to 1914, the method and equip- 
ment used had not been fully developed or standardized and conse- 
quently no note is taken here of results obtained previous to the 
milling of the 1915 crop samples. The chief source of the varietal 
samples since 1915 has been the numerous experiment stations and 
substations located in the western United States. The data presented 
in this bulletin contain the results obtained only during the seven 
years from 1915 to 1921, inclusive, 2 
The milling and baking experiments with varieties from experi- 
ment stations were begun in 1915 upon a uniform set of spring wheat 
varieties from eight stations in the Great Plains area. Since 1917, 
samples of varieties from five stations in the Pacific Coast area and 
samples of winter wheat varieties from additional stations in the 
western half of the United States have been included. 
The commercial samples in recent years have largely been ob- 
tained from grain supervisors in the several Federal grain supervi- 
2 The milling and baking experiments were conducted from 1915 to 1917, in the then 
Office of Grain Standardization of the Bureau of Plant Industry in the milling labora- 
tory operated at Fargo, N. Dak., in cooperation with the department of chemistry of the 
North Dakota Agricultural Experiment Station. Since 1918 the laboratory has been 
located at Washington, D. C, and the experiments have been conducted by the section of 
Milling Investigations of the Grain Division, Bureau of Agricultural Economics. The 
Office of Cereal Investigations, Bureau of Plant Industry, cooperated by furnishing \arie- 
tal samples. 
