WORK OF THE SAN ANTONIO EXPERIMENT FARM IN 1912. 13 
The results from subsoiling in 1912: were corroborative of those 
of previous years, namely, that subsoiling does not materially in- 
crease the yields of crops, and in many instances decreases the yields, 
and that, owing to its being an expensive operation, it can not be rec- 
ommended as a regular farin practice in connection with corn, oats, 
and cotton in the San Antonio region of Texas. 
ROOT-ROT. 
Root-rot. a fungous disease of plants,? is doubtless one of the most 
9 tes) 9 
serious diseases with which farmers have to contend in the Black 
Lands of Texas. It affects such crops as cotton, cowpeas, and alfalfa, 
Fic. 4.—Cotton on plat B 5-4, land continuously cropped and fertilized each year with 
barnyard manure. This plat has yielded an average of 455 pounds of seed cotton per 
acre during the past three years. Compare with figure 3. (Photographed June 26, 
1912.) 
but does no perceptible damage to plants belonging to the grass fam- 
ily, such as corn, oats, wheat, ete. In many cotton fields it causes the 
premature death of a large proportion of the plants. It was observed 
in 1912 that in a number of the rotations with cotton and corn the 
root-rot was much more widespread and did more damage to the cot- 
ton on plats which were spring-plowed than on plats which were 
summer or fall plowed. The same condition was apparent in 1911. 
It was also observed in 1912 that where cotton was grown in rota- 
tion with corn or oats the damage due to root-rot was much less 
noticeable than on plats continuously planted to cotton. 
1 This disease is caused by Ozonium ominivorum. For an account of the disease and 
methods of lessening its damage, see the paper entitled ‘‘ The control of Texas root- 
‘rot of cotton,’ in Bureau of Plant Industry Bulletin 102, 
Peir b20i] 
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