30 MISC. PUBLICATION 273, U.S. DEPT. OF AGRICULTURE 



plants. The larvae hibernate at depths of 6 to 14 inches below 

 the surface of the ground. In the spring the larvae resume feeding 

 and do their greatest injury to roots as they work upward. The 

 full-grown larvae pupate in the soil and emerge as new adults late 

 in the spring and summer, mostly during June and July. 



Seedbeds can be protected from infestation by encircling them 

 during the migration and egg-laying period with barriers, such as 

 boards or metal strips placed on edge in the ground and painted 

 with sticky substances such as coal tar or tree-banding material, 

 or by spraying with DDT to kill the migrating adults. Poison 

 baits, containing 5 pounds of powdered calcium arsenate or sodium 

 fluosilicate and 95 pounds of ground dried-apple waste, applied at 

 the rate of 50 to 70 pounds per acre, have proved effective in large 

 fields. 



Infestations may be prevented through clean cultivation and 

 rotation of seed and transplant beds, allowing infested plots to 

 remain fallow and be cleanly cultivated in alternate years. 



WIREWORMS 



Under certain conditions wireworms (Elateridae) (83) may 

 prove to be troublesome nursery pests. They are most frequently 

 found in heavy, moist soil, where they feed on undecayed plant 

 material and small roots. These long, slim, cylindrical, hard-shelled 

 "worms" with feebly developed legs are the larvae of click beetles, 

 which can be easily recognized by their ability to flip into the air 

 for several inches when turned on their backs. 



The new soil fumigants D-D and ethylene dibromide have 

 proved effective in wireworm control. D-D is applied at the rate 

 of 400 pounds (40 gallons) per acre at a depth of 6 to 8 inches, 

 and ethylene dibromide at 10 percent by volume (or 20 percent 

 by weight) strength dissolved in a naphtha 200-base thinner at 

 the rate of 20 gallons per acre. These soil fumigants are applied 

 at least 15 days before planting, v/hen the soil is not too wet or too 

 dry and the temperature at the 8-inch depth is not below 50° F. 



CUTWORMS 



From time to time cutworms make their appearance in forest 

 nurseries and do considerable damage to the young trees by feed- 

 ing on the roots or clipping off seedlings at the ground line. 



The adults of cutworms are the dull-colored, yellow, tan or 

 brown moths that collect around lights at night and are commonly 

 referred to as "millers." They fly at night, usually early in the 

 spring, and lay their eggs on the ground where there is ample 

 vegetation for larval food. The larvae, or cutworms, work under- 

 ground, feeding on the roots of various plants, or during the night 

 they often feed above-ground on the foliage or clip off the stems 

 at the ground line. They are dull-colored, with few or no hairs on 

 the body, and some have a greasy, slimy appearance in keeping 

 with their ground habitat. They reach full growth late in the sum- 

 mer or in the fall and overwinter in the soil as full-grown larvae 



