CEREAL EXPERIMENTS AT CHICO, CALIF. 7 
June, July, August, and frequently also September are prac- 
tically rainless. Table 2 shows the number of times each month was 
rainless during the 51-year period from 1871 to 1921. 
Table 2. — Average monthly, seasonal, and annual precipitation and number of times 
each month ivas rainless at Chico, Calif., during the 51-year period from 1871 to 1921. 
Month. 
Sea- 
sonal 
An- 
nual. 
Character of data. 
Jan. 
Feb. Mar. 
Apr. 
May. 
June. July. 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
(Sept. 
to 
May). 
Precipitation: 
Average 
Times rainless 
5.00 

3.79 3.22 
1 
1.58 
5 
1.00 
8 
0.39 
25 
0.04 
46 
0.02 
42 
0.60 
21 
1.18 
11 
2.67 
3 
4.20 
1 
23.24 
23.69 
Table 3 shows the monthly, annual, and seasonal precipitation, 
with averages and maxima and minima in the 12-year period from 
1910 to 1921, inclusive. The average annual precipitation was 24.62 
inches and the seasonal 24.61 inches in the 11 years, which are approxi- 
mately 1 inch greater than the corresponding averages for the 51- 
year period. Frequently very heavy monthly rainfall is recorded 
during the wet season. In 1911, 1914, and 1916 the January rain- 
fall was 11.39, 10.51, and 12.48 inches, respectively, and in November, 
1920, it was 10.68 inches. All but one of these seasons of excessive 
monthly rainfall have been reflected in reduced yields. On adobe 
lands during such seasons there is much drowning of grain, owing to 
poor soil drainage and standing water. 
Table 3. — Monthly, annual, and seasonal precipitation at Chico, Calif., in the 12-year 
period from 1910 to 1921, inclusive. 
[Precipitation data in inches. 
T= trace. The seasonal averages are for the period from September to May, 
inclusive, for the 11 years shown.] 
Year. 
Jan. Feb. Mar. Apr. May. June. July. 
1910 3.77 2.49 3.62 0.23 0.06 0.05 
1911 11.39 2.04 5.86 1.43 .17 .20 
k 1912 3.27 .69 3.70 2.14 1.80 .12 
1913 4.53 .82 2.41 1.16 1.39 1.01 
1914 10.51 6.27 .57 1.83 .36 1.87 
1915 9.15 10.33 2.14 .93 3.22 
1916 12.48 3.28 ,1.91 .27 1.45 .80 
1917 3.18 4.75 1.28 1.97 2.64 
1918 1.01 4.74 5.41 .90 .70 T 
1919 3.38 7.36 3.37 .78 .10 
1920 47 2.86 5.06 1.87 T .09 
1921 7.91 ( 1.84 2.24 .53 .94 T 
Average 5.92 3.96 3.13 1.17 1.07 .35 
Maximum . . 12. 48 10. 33 5. 86 2. 14 3. 22 1 . 87 
Minimum... .47 .69 .57 .23 T 
S3 
Aug. Sept. Oct. ! Nov 
.07 
0.71 
.12 
4.84 


T 
.40 
.34 
3.49 
.90 

.014 .90 
.10 4.84 

0.50 
.31 
1.23 

.88 
.02 
2.10 

.88 
.36 
1.90 
.96 
0.86 
.10 
3.14 
7.27 
.53 
1.85 
2.09 
1.58 
I 2.48 
.77 
10.68 
Dec. 
An- Sea- 
nual. sonal. 
1.77 
2.01 
1.02 
9.42 
5. 55 
6.85 
4.94 
1.77 
1.82 
4.72 
7.67 
6.43 
14.06 . 
23.63 
21.95 
28.10 
28.37 
34.49 
29.85 
17.61 
21.43 
21.74 
30.68 
23.57 
24.73 
14.14 
20.54 
36.23 
32.73 
28.11 
23.35 
16.45 
23.66 
17.01 
33.71 
.76 I 2.84 
2.10 10.68 
.10 
4.50 24.62 24.61 
9.42 34.49 36.23 
1.02 14.06 14.14 
Temperature. 
Mean, maximum, and minimum temperatures at Chico from 1910 
to 1921 are shown in Table 4. The period of growth and ripening of 
cereals extends from about the middle of March to early in June. 
Temperatures usually remain cool through April and part of May, 
but late in May they generally rise rapidly, causing grain to ripen 
quickly. Midseason varieties of wheat and barley usually ripen in 
6 to 8 days, and early varieties in 10 to 12 days. Unusually high 
