36 ANNUAL REPORTS 01 DEPARTMENT OF AGRICULTURE, It) 
69 fields of 2,51 1 acres. Approximately I pounds of dust 
taining LO percent of DDT, sufficient benzene bexachloride to L r 
percent of the gamma isomer, and 40 percent of sulfur were 
These fields received from one to six dustings, depending upon the 
infestation and fruiting of the plants. High, dry wind- prevailed 
while much of this work was in progress. Consequent!? results were 
not so favorable as desired, although some build-up of infestation in 
early bolls was prevented. Since drought prevented the setting of 
Late bolls in many of the fields in dry-lancl areas, the benefits may 
have been considerable. 
Whereas these control programs are intended to suppress outbreaks 
of the pink bollworm and thus prevent spread of the Dest, they also 
serve as demons! rat ions of the value of such work by individual grow- 
ers. In the heavily infested Presidio Valley of Texas, for example, 
growers who saw the work there are now using the same methods and 
arc obtaining good results. 
Four thousand tons of plant ing cottonseed were treated in a Federal- 
State cooperative program in Texas, principally for growers in An- 
drew-. Gaines, Midland. Martin, and Howard Counties, and the west- 
< rn part of Mitchell County. This program supplemented the dusting 
program undertaken there to suppress the serious infestation that 
developed in ID 17 and 1948. 
Compliance with State field clean-up requirements in the Lower Rio 
Grande Valley of Texas was incomplete, as over ."in growers there were 
charged with violation of the State pink bollworm law. However. 
that number is a very small percentage of the 6,343 growers who 
planted cotton under permit on 600,854 acres. 
Estimates of increased yield in the Lower Bio Grande Valley place 
a value of more than $10,000,000 annually on the incidental benefits 
from control of other cotton insects, particularly the boll weevil, re- 
sulting from the rigid cultural practices required for pink bollworm 
control. Before the value of establishing a host-free period was 
cepted by the growers, it was necessary to use public funds to remove 
volunteer plant-, but now many growers are u-inL r thousands of mam- 
day.^ of labor cadi fall to grub out volunteer cotton while others may 
replow several times in order to kill all sprouting cotton. Examina- 
i ion of crop residues on the .-oil surface in a number of fields in south- 
ern Texas in March and April of L949 revealed living pink bollworms 
in seed in old cotton bolls. Failure of the L r rower< to cover such resi- 
dues by plowing deep enough to prevent emergence <»f overwintering 
pink- bollworm- i- responsible for this survival The cleaning of cot- 
ton field- by certain date- was a bo required by State regulation in the 
i ther quarantined area- in southern Texas, and on the whole a satis- 
factory pink' bollworm host-free condition was maintained, although 
a number of growers were delayed beyond the stalk-destruction dead- 
line by reason of excessively wet fields. 
The Slate of Arizona again prohibited the growing of stub cotton 
m the southern and eastern portions <>f the Salt River Yallev. The 
Bureau participated in locating and removing -tub cotton plants to 
prevent the pink bollworms from having an early supply of food. 
