24 BULLETIN 1172, U. S. DEPARTMENT OF AGRICULTURE. 
Previous to this time the work in wheat improvement at Chico had 
been confined to a limited amount of selection to obtain pure lines. 
Most of the crosses made at Chico to develop improved varieties for 
the great sections which produce winter or spring wheat are now being 
grown at various experiment stations throughout those areas. 
The objects for which the crosses at Chico have been made are 
winter hardiness, rust resistance, smut resistance, earliness, and 
quality as well as a number of such factors as stiffness of straw and 
nonshattering habit. The leading parent varieties used are as 
follows: For winter hardiness, Bunum No. 17, Minhardi, and Min- 
turki; for rust resistance, Kota and Kanred; for smut resistance, 
Hussar and Martin; for earliness, Sunset and Hard Federation; and 
for high milling quality, Marquis and Hard Federation. A total of 
34 different varieties was used in the 66 combinations made. 
A total of 8,889 apparently crossed kernels have been harvested. 
Less than 1 per cent of the kernels have been found not to be crosses. 
Approximately 2,950 florets were emasculated in 1919, 3,000 in 1920, 
and 9,816 in 1921, with 1,210, 1,293, and 6,386 kernels, respectively, 
harvested in the successive years. The percentages of successful 
crosses closely approximate 45, 42.1, and 65.1, respectively, in the 
three years. In 1920 the percentage was lowered by a number of 
sterile spikelets which had been pollinized in experiments with 
stored pollen. 
BARLEY EXPERIMENTS. 
Barley is the most important grain crop of the Sacramento Valley. 
Approximately three times as much barley as wheat is produced 
annually. It matures more quickly and yields greater returns than 
wheat on a large class of soils. It is the principal grain feed of the 
section for horses and mules and is used also to some extent as a hay 
crop. 
Barley is well adapted to the climate. Its growth and develop- 
ment occur during the latter part of the cool wet season, and it 
usually reaches maturity before the heat of summer arrives. The 
crop is sown in late fall, winter, or early spring. Spring varieties 
sown in the fall survive the winter equally as well as winter varieties. 
With the exception of Rhynchosporium, or "leaf scald," barley 
in the Sacramento Valley is unusually free from plant diseases. Most 
varieties are susceptible to the disease. Susceptible plants are 
infected in the early as well as in the later stages of growth. 
Varietal Comparisons. 
PLAT EXPERIMENTS. 
Ninety-two varieties of barley have been grown in the plat experi- 
ments in one or more years during the 12-year period from 1910 to 
1921, inclusive. These have included the principal varieties from 
other barley-producing sections in the United States and also many 
varieties from other countries. The annual yields of 30 of these 
varieties in some or all of the 12 years, with average yields expressed 
in percentages of the yield of Coast barley (C. I. No. 690) in the same 
years, are given in Table 10. The remaining varieties are listed by 
name and number in Table 11. 
Coast and Beldi were the only varieties grown in all of the 12 years. 
The average acre yield of Coast was 48 bushels and of Beldi 44.9 
bushels. Coast, together with several varieties of the Coast type, 
