Geass Insects 569 



medium-sized, dull-colored, snappiii<>; beetles or click beetles. 

 They are underground insects that injure the plants by feeding 

 on their roots. There are several species that injure grass in the 

 state, the most important of which are, the wheat wireworm 

 (Agrio'tes mancus Say), the corn wireworm {Melanotus communis 

 Gyllenhal), Drasterius elegans Fabricius, and several others. The 

 beetles appear in May and June and the females deposit their 

 eggs in the soil. The beetles are from on&-third to one-half inch 

 in length, dull grajish-brown in color, and have the peculiar habit 

 of snapping themselves into the air when laid on their backs. The 

 young wireworms feed on the grass roots for several seasons, the 

 various species differing in the length of their life cycle from 

 three to six years. The wireworm larvae reach maturity early 



Fig. 611. A Wireworm. Two and One- 

 Half Times Natural Size. 



in July. They are then from one-half to one and one-half inches 

 in length, depending on the species. They transform to delicate 

 whitish pupae in earthen cells within six inches of the surface of 

 the ground. Transfomiation to the beetle takes place in from 

 three weeks to a month, the beetles remaining within the earthen 

 cell until the following spring. 



Control. Clover and buckwheat are not so subject to wireworm 

 attacks as most other crops. When these crops are grown their 

 presence tends to decrease the number of wireworms in the field. 

 In grass land the amount of wirewonn infestation usually 

 increases with the length of time during which the field is left 

 in sod. An excessive wireworm infestation may be avoided by 

 not leaving fields in grass for more than two or three years, a 

 measure also recommended for the prevention of white grub injury 

 and one in line with good agricultural practice. 



THE ARMY-WORM 



Heliopliila unipuncta Haworth 



Although army-worai outbreaks occur only at intervals of sev- 

 eral years the insect is present in our meadows every season. 



