10 CIRCULAR NO. 120, BUREAU OF PLANT INDUSTRY. 
TABLE I.—NSunemary of meteorological observations at the San Antonio EH.rperi- 
ment Faria, L907 to 1912, inclustve—Coutinued. 
TEMPERATURE (°F.). 
= 
| | | | Total 
em: Jan. | Feb. | Mar. | Apr. | May.| June.| July.| Aug.| Sept.| Oct. | Nov.| Dec.! for 
| | | period 
| 
| | 
Absolute manxi- | 
mum, 6 years, | 
1907 to 1912, in- 
GIUSIMGa 2-2-4522 88.5 | 87.0-| 95.0 |102.0 |103.0 |108.0 |108.0 |105.0 |104.0 | 98.0 | 86.5 | 82.0 | 108.0 
Absolute maxi 
mim, 191222522. 84.0 | 78.5 | 82.0 | 90.0 |103.0 |100.5 }105.0 |104.0 {101.0 | 94.0 } 84.0] 74.0] 105.0 
Absolute minimum, 
6 years, 1907 to 
1912. melusive:...| 1250 4) 1320: | 34.0 |°38:0 | 39.0: | 5620)) 76420 | 6420} 4170" | 3220 De OR eligi) 12.0 
Absolute minimum, 
169) 2 a eee er 1655 }' 16..0)), 34.0 | 38:0) 4720) | 59:0 )| 6650) | 68.0 1154. bso On 2580 P2550 16.0 
Mean, 6 years, 1907 : 
to 1912, inclusive.-| 54.1 | 54.7 | 65.0 | 68.6 | 75.2 | 82.7 | 85.2 | 85.3 | 80.3 |-69.6 | 59.6 | 50.2 €9.2 
Mean, 1912......... 46.6 |.49.9 | 55.4 | 67.4 | 76.5 | 77.8 | 85.1 | 86.8 | 82.0] 71.8 | 59.4 | 48.6 iors} 
KILLING FROSTS. 
Last in spring. First in autumn. 
| = Length 
Years. Mini- Mini- ee ah le 
mum ; mum = 
Date. temper- Date temper- period 
ature. ature. 
°F el Days 
10910 VFp js st ec et ee Ae ETOP Feb. . 8 29 Nov. 12 32 217 
S105 55 cesar Ae peta ee ae ee Feb. 20 24 Nov. 14 29 268 
ISTO) es me ek ee ar ea gS Feb. 25 30 Dec. 6 31 284 
CIC Rpm eee ssacr ae OY een ne Ngee, aye eye, eee ee Cones: 26 Oct. 29 32 246 
THU Ze eae ae ee EE me ee ee eee doses 29 Nov. 13 31 261 
TES. 5, a rr co aS Feb. 27 30.5 | Nov. 2 29.5 245 
ROTATION AND TILLAGE EXPERIMENTS.’ 
The rotation and tillage experiments, which are conducted on 82 
plats of one-fourth of an acre each, were continued as previously, 
except that milo was substituted for corn on four plats and for oats 
on one plat. 
The results of the rotation exper mene indicate that crop rotation 
is an important factor in crop production in this section of Texas, 
the vields of crops grown in a suitable rotation being on the whole 
uniformly higher than when grown continuously on the same land. 
The average yields of all crops except cotton were the highest of any 
year since the work was started in 1909. 
Table IT gives the crops in the rotation experiments, the number of 
plats planted to each crop in 1912, the average yields per acre, and 
the highest and lowest yields per acre in 1912. 
1These experiments are under the direct supervision of Mr. C. R. Letteer, assistant. 
[Cir. 120] 
