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The application of rotenone suspensions on the tacks of cattle 
was greatly expedited and simplified by use of a power sprayer and 
a regular orchard gun, the spray having been directed -vertically 
downward on the baoks of the cattle in an ordinary cattle chute. The 
spray recommended consisted of cube or derris powder (5 percent of 
rotenone) 5 pounds, wettable sulfur 10 pounds, and water 100 gallons. 
This method would appeal especially to owners of large ranch herds.— 
Wells (672). 
Cube-sulfur wash may be applied to the baoks of the cattle with 
a brush.— Laake and coworkers (348 ) • 
Cube and derris powders applied dry in combination with wettable 
sulfur were fully as effective as when they were applied as washes 
or sprays. The dust mixture was not so effective as the wash on cattle 
with dense coats of hair, but it can be applied more rapidly than the 
wash and it had found favor with the owners of small farm herds and 
dairy herds.— Laake (347 ) ; Wells and Laake (673 )„ 
Ox warbles might be satisfactorily controlled by placing range 
cattle in chutes and spraying them with 10 pounds of wettable sulfur, 
10 pounds of derris (5 percent of rotenone) to 100 gallons of water 
to which a detergent should be added. This spray was not effective 
in controlling these grubs in dairy cattle when applied as a wash with 
a stiff brush.— Stewart (569) . 
In Idaho both species of cattle grubs are common and the control 
methods are fully described, including the hand wash method, hand dust 
method, and power sprayer method.— Shu 11 and Fisher (640 ) i U. S. De- 
partment of Agriculture (632 ). 
The oft-recommended procedure of extracting the grubs by hand 
and the chemical methods of oontrol are effective only after the grubs 
perforate the hide for their oxygen supply. For large herds a rote- 
none preparation consisting of 12 ounoes of cube or derris powder and 
6 ounces of wettable sulfur per gallon of water make a very effec- 
tive wash for application to the backs of oattle.— Thorns sen and Doner 
(691). 
There is no known substitute for rotenone in the treatment of 
large numbers of animals infested with cattle grubs. Extracts of 
derris or ground derris root diluted with pyrophyllite or tripoli 
earth to a rotenone concentration of 1.25 percent was reoomBended.— 
U. S. Bureau of Entomology and Plant Quarantine (628) . 
