Alfalfa in Kansas. 



369 



History and Distribution. 



This insect, which is of foreign origin, was first noticed in the 

 country in 1876, when the beetles were found about the roots of grass in 

 New Jersey. It is now widely distributed over the United States. It 

 occurs more often on clo.ver growing along roadsides, but within the last 

 few years it has been found doing serious injury in several parts of the 1 

 country. 



FIG. 313. Clover-root 

 curculio (Sitones hispidu- 

 lus). Adult; greatly en- 

 larged. (After Wilder- 

 muth, U. S. Dept. Agr.) 



FIG. 314. Clover-root 

 curculio. Larva ; greatly 

 enlarged. (After Wilder- 

 muth, U S. Dept. Agr.) 



Habits and Life History. 



The following paragraphs relating to the life history of the clover- 

 root curculio are taken in substance from Mr. Wildermuth. 2 



The clover-root curculio passes the winter in the adult form, hiding 

 under rubbish and leaves close to the ground. With the first warm days 

 of spring the beetles come forth and the females begin to lay their eggs 

 upon the plants on the roots of which the larvae are to feed. The adults 

 feed on the leaves, eating out irregular patches from the margin of the 

 leaf. (Fig. 315.) The adults endeavor to escape injury by feigning 

 death. If the leaf upon which the beetle is feeding or resting is touched 

 the beetle drops to the ground and lies there as if dead. The eggs may 

 not only be laid on the under side of the clover and alfalfa leaves, but 

 may also be laid on the ground near the plant. The eggs when first laid 

 are whitish, but within less than a day change in color to shiny black. 

 In about two weeks the eggs hatch and the larvae immediately go down 

 into the ground. 



At first the larvae feed on small, tender, fibrous roots, but as they 

 reach maturity they attack the larger roots, eating large cavities or 

 grooves into them. (Fig. 315.) Within about three weeks the larvae are 

 full grown, and after making an earthen cell pass into the pupal stage. 

 The pupal stage is from eight to ten days. There seems to be only one 

 generation of this insect annually. Although the clovers have appeared 



2. Bu'l. 85, pt. Ill, Bu. Ent., U. S. Dept. Agr. 



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