WORK OF THE SAN ANTONIO EXPERIMENT FARM IN 1912. 13 



The results from subsoiling in 1912 were corroborative of those 

 of previous j-ears, 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 farm 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 

 serious diseases with which farmers have to contend in the Black 

 Lands of Texas. It affects such crops as cotton, cowpeas, and alfalfa, 





Fig. 4. — Cotton on plsit B 5-4, land continuously cropped and fertilized each year with 

 harnyard manure. This plat has yielded an average of 4r)r) pounds of seed cotton per 

 acre during the past three years. Compare with figure :'.. (Photographed .Tune 26, 

 1912.) 



but does no perceptible damage to plants belonging to the grass fam- 

 ily, such as corn, oats, wheat, etc. 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 si^ring-ploAved 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 0.:uniiiiii uitniironuii. For an account of tlie diseusc 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. 

 [Cir. 120] 



