70 PAPERS ON INSECTS AFFECTING VEGETABLES. 
usually exceeds $5 a ton. As previously mentioned, a defoliation by 
the sugar-beet webworm may reduce the yield of sugar beets 1 to 5 
tons to the acre and also cause a loss in sugar content and purity. 
As this damage can be absolutely prevented at a cost not exceeding $2 
an acre, the profits from spraying infested beets are apparent. 
CONCLUSION. 
An easily accessible supply of water will aid materially in keeping 
down the cost of spraying. Water from the irrigation laterals 
may boused, but in all cases it should be carefully strained to pre- 
vent dirt and other material from getting into the pump and clogging 
the nozzles. Water that is highly charged with alkali should be 
avoided. 
After a sprayer is used it should be carefully washed with clean 
water and all the working parts thoroughly oiled. It is a mistake to 
allow a sprayer to stand in the field exposed to sun and weather, and 
it will pay to keep it housed when not in actual use. 
As a final word, it may be well to state that webworms, and with 
few exceptions most other insects which affect sugar beets in the 
Arkansas Valley, can be easily and cheaply controlled. When this 
fact is more generally accepted by the beet growers it is safe to say 
that sugar beets will produce still better profits. 
ADDITIONAL COPIES of this publication 
ii- may be procured from the Superintend- 
ent of Documents, Government Printing 
Omce, Washington, D. C, at 5 cents per copy 
