INSECTS INJURIOUS TO CLOVER 



213 



three weeks or more, and the flies of the second generation appear 

 in Central Illinois in late July and early August, being abundant 

 as the second crop of clover heads appear. The eggs are laid 

 in the clover heads and hatch in about three days, and the second 

 generation of maggots do the worst damage to the seed in late 

 August and early September, in the same manner as did the first 

 generation. They become full grown by frost and hibernate 



FIG. 152. The clover-flower midge (Dasyneura leguminicola) : a, enlarged 

 side view of female, with scales denuded, to show more clearly the struc- 

 ture; b, head, more highly magnified, to show structure of the eye, 

 palpi, and basal joints of antennae; c, tip of ovipositor, highly magnified 

 and showing at end of next to last joint the manner in which it is clothed 

 with minute hairs; d, highly magnified antennal joints, their minute hairy- 

 clothing shown on the lower one; 2, a, larva enlarged, ventral view; 

 b, head retracted, highly magnified. (After Riley.) 



either as full-grown larvae, in which case they pupate early the 

 next spring, or pupate before frost and pass the winter as pupae in 

 the soil. 



Control. Fortunately this pest may be very readily controlled 

 by adapting the methods of harvesting so as to destroy the devel- 

 oping maggots. If clover is grown alone it should be cut early, 

 before the maggots have become mature. This results in drying 

 up the food plant and thus destroying the larvae and hastens the 

 development of the second crop of clover heads, so that the midges 



