Alfalfa hooper 



NATURE OF INJURY 



The injury to sugar beets is similar to that caused by other leaf- 

 eating caterpillars. The destruction of the leaves reduces the yield and 

 sugar content of the crop. 



Both the leaves and blossoms of alfalfa are eaten. This reduces the 

 yield and quality of hay. The destruction of the blossoms reduces the 

 yield of seed where the crop is grown for seed production. 



METHODS OF CONTROL 



As this insect seldom if ever attacks sugar beets until its favorite 

 food plants (alfalfa and sweet clover) are exhausted, such attacks can be 

 anticipated and preventive measures employed to protect the crop. 



Furrow Trap 



In case sugar beets adjoin infested alfalfa or waste land overgrown 

 with sweet clover the furrow trap recommended for the control of the true 

 army worm (page 79) can be used with good results. The furrow should 

 be thrown away from the beets so as to leave the perpendicular side next 

 to them. If water is available a small stream in the furrow will add to 

 its effectiveness. 



Poisons 



Where the loopers are feeding on alfalfa or sweet clover growing on 

 ditch banks or fence rows about beet fields these plants should be sprayed 

 with Paris green or arsenate of lead, using 2 to 3 pounds of the former or 

 8 to 1 2 pounds of the latter if the paste is used, or 4 to 6 pounds of the dry 

 form, to 50 gallons of water. 



If the caterpillars have entered a beet field, spray the beets, using 

 the proportions of poison and water given above. 



Bunches of freshly cut green alfalfa or sweet clover, sprayed with 

 Paris green and placed in the furrow, where the furrow trap is used, will 

 kill many of the loopers. 



Mowing 



Where alfalfa is being damaged it should be mowed at once. The 

 longer it stands the poorer the quality will be. After the hay is removed 

 the stubble should be sprayed to destroy the worms and protect the new 

 growth. 



If strips of alfalfa are left uncut at intervals through the field the 

 loopers will congregate on these and can then be killed by spraying the 

 standing alfalfa. When the worms have been destroyed the alfalfa on 

 the strips can be removed. This hay should not be fed unless heavy 

 rains have washed off the poison. 



Close watch should be kept of the worms after the infested hay is 

 cut to prevent their migrating to adjoining crops. 



DESCRIPTION 

 The Egg 



The eggs are pale yellow, hemispherical in shape, rounded at the base, 

 the apex with a rounded depression, and are finely creased vertically.* 



*J. A. Hyslop. "'The Alfalfa Looper." Bulletin No. 95, Part VII. Bureau of Entomology. U. S. 

 Department of Agriculture (1912). 



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