RICE EXPERIMENTS IN CALIFORNIA. 59 
Manure is too scarce and difficult to apply for commercial use, but 
sulphate of ammonia, dried blood, or cottonseed meal can be cheaply 
applied, and the results indicate that either of these substances may 
be used profitably on commercial rice fields in California. 
The varieties of rice most commonly grown in the United States 
are roughly classed as long grain, medium grain, and short grain. 
About 98 per cent of the rice grown in California consists of short- 
grain varieties. 
The varieties of rice which belong in each class can be grouped 
according to maturity, as early, midseason, and late. 
During the 9-year period 1913 to 1921, inclusive, many varieties 
and selections of rice have been grown in the nursery and plats at 
the Biggs Rice Field Station. 
The varietal experiments indicate that the long-grain and medium- 
grain varieties are not well adapted, while the short-grain rices are 
well suited to California conditions. 
Thirty-five varieties and strains of rice have been grown in tenth- 
acre plats and 9-year average yields obtained for seven varieties. The 
variety giving the highest average yield in the nine years was Watari- 
bune, C. I. No. 1561, a late-maturing short-grain rice, yielding 4,364 
pounds per acre. The Butte, C. I. No. 1564, a midseason short-grain 
variety, produced an average yield for the same period of 3,456 pounds 
per acre. Honduras, C. I. No. 1643, a long-grain late-maturing vari- 
ety, produced an average yield for the same period of 2,600 pounds 
per acre. 
During the 4-}'ear period 1918 to 1921, the highest yielding variety 
or selection in the short-grain early group was Sue Hero, with an aver- 
age yield of 1,843 pounds; in the midseason group, Selection No. 
1561-3, 3,920 pounds; and in the late group, Selections Nos. 114 and 
115, 2,995 pounds per acre. For the same period Early Prolific, a 
medium-grain midseason variety, produced an average yield of 2,337 
pounds, and Selection No. 113, a long-grain midseason variety, 2,612 
pounds per acre. 
Early rice varieties mature in from 135 to 154 days from the date 
of the first irrigation, midseason varieties in about 161 days, and late 
varieties in 176 to 180 days. 
Several hundred varieties and selections have been grown in the 
station nursery during the past eight years. Those varieties or selec- 
tions which yield well in the rod-row nursery usually yield well in 
plats and larger fields. 
The leading commercial rice varieties in California are Early Watari- 
bune, Colusa (C. I. No. 1600), Onsen, Caloro, and Late Wataribune. 
Barnyard grass (Echinochloa crusgalli and varieties) is the worst 
weed in the California rice fields. The methods of control consist of 
hand pulling, cultivation during fallow years, and continuous sub- 
mergence from date of seeding until the rice crop is ready to drain. 
Other weeds which are troublesome at times are scale-grass, spike 
rush, cat-tails, umbrella plants, and canary grasses. 
Beans, corn, grain sorghums, cotton, and hemp have not boon 
grown successfully, due to a high water table during the growing 
months. Wheat and barley appear to be the best crops to rotate 
with rice. 
