CLOVER CULTURE. 



115 



and it now only remains to treat of the clover hay worm, leav- 

 ing- those that infest the seed to be considered in "Chapter XII. 

 The clover hay worm, (Asopia costalis), Fabr., belongs to 

 the same family as the moth that infests bee hives and the moth 

 common in meal. The illustration herewith given will 

 enable our readers to identify the worm. In it, as described 

 by Prof. Cook, 1 and 2 represent the larvae suspended by 

 threads of their own spinning 1 , 3 represents the cocoon, 4 the 



chrysalis, 5 the moth 

 with wing's spread, 6 the 

 moth at rest, and 7 the 

 larvae concealed in a case 

 of silk which it ha? 

 spun. The eggs are 

 laid on the clover. The 

 larvae work in a silken 

 case and thus often ma1 

 the hay into a great 

 mass. They may be 

 seen in summer working 

 on hay, but more usually 

 in February or March, 

 when stacks and mows 

 may be fairly alive with 

 larvae. They often crawl into the stack to protect them- 

 selves from the cold. The color of the larvae is dark brown, 

 the cocoon is white and the chrysalis yellow, the moth purple 

 with a silken luster ancf it has two bright spots on the wings. 

 Prof. Riley described the insect at an earlier date in the 6th 

 Missouri Report. Prof. F. M. Webster, of Wooster, Ohio, 

 special agent of the Department of Agriculture, in "Insect 

 Life," (volume 4, numbers 3 and 4, November 1891,) paid^a, visit 

 to the farm of Prof. W. I. Chamberlain on April 27th, 1891, 

 for the purpose of investigating this worm at work. The hay 

 was in an open stack and was damaged twenty per cent. It 

 was found that the majority of the larvae could be killed by 

 re-stacking the hay and dusting it with two pounds of pow- 

 dered pyrethrum, mixed with ten pounds of flour, to each ton of 

 hay. A number of larvae were taken from this hay and 

 placed in breeding cages. They continued to feed on the 

 dry hay for a considerable time, the pupa being first 

 observed on May 25th, and moths beginning to issue on 

 June 12th. The eggs appeared to be laid on the heads 

 of growing clover and about July 1st the young larvae 

 appeared. It would seem from this that the eggs may be 

 deposited on the plants in the field and thus the larvae 



THE CLOVER HAT \\ORM. 



