BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 23 
pected in several areas of Montana, especially the north-central region, 
and in western North Dakota. Serious and widespread outbreaks 
are anticipated for southwestern South Dakota, northwestern Ne- 
braska, northeastern Colorado, southern and northeastern California, 
southeastern Oregon, and northwestern Nevada. Troublesome in- 
festations in 1951 are forecast for scattered areas of Idaho. Arizona, 
Minnesota, New Mexico, Utah, Kansas, Oklahoma, and Texas. 
Mormon Crickets Controlled 
Widespread infestations of Mormon crickets did not develop in the 
Western States, although conditions were favorable for cricket in- 
crease and spread, as shown by a noticeable build-up in several coun- 
ties of Montana. Utah. South Dakota, and Wyoming. Mormon 
crickets displayed a banding tendency and a distribution pattern 
similar to that in the late 1930's, when the insect reached major out- 
break proportions. 
Early baiting operations on ranges in Colorado, Montana, Nevada, 
Oregon. Utah, and Washington were adequate to protect crops and 
range forage, resulting in only slight damage by the Mormon cricket. 
This work was done in cooperation with other Federal agencies, 
States, counties, and landowners. Most of the baiting was done on 
the Federal domain. More than 68,000 acres of range lands were 
baited — 13.500 acres by airplane, 24.800 by ground equipment, and 
120 by hand. Two hundred and forty-five tons of bait was spread 
in the operations. Owing to early and adequate work by the co- 
operators, damage to crops and range forage was slight in 1950. 
Late-summer surveys in 1950 indicated that infestations needing 
control in 1951 would probably develop in several parts of Utah, 
Nevada, Oregon, and Washington. 
Better Protection From Insects Provided for Stored Grain 
Insectproofing of bags received further study in cooperation with 
the Bureau of Agricultural and Industrial Chemistry. Cotton bags 
and 14-ounce burlap bags treated with a mixture of pyrethrins and 
piperonyl butoxide have given protection from insect penetration for 
14 months. It is now necessary to find some means of binding the 
insect repellent to the bag fabrics so that flour or other products packed 
in the treated bags will not become contaminated. Fiberboard cartons 
sealed with an adhesive containing a mixture of the same chemicals 
have repelled insects for as long as 9 months. 
Tests have demonstrated that fogging with an insecticide may have 
a definite place in a program of flour-mill insect control and also 
may be an effective method of destroying insect infestations in rail- 
way boxcars. In the fogging of mills large numbers of insects were 
killed but the insecticide did not reach those that were hidden in the 
flour stock. 
The tests were conducted under Research and Marketing Act funds. 
A new fumigant mixture of 1 part of bromotrichloromethane and 
19 parts of carbon tetrachloride, used at the rate of 1.5 gallons to 
1.000 bushels of wheat in steel farm bins and at 2 gallons in wooden 
bins, gave 100- and 89-percent kills, respectively, of adult grain in- 
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