DEVELOPMENT 



The white-fringed beetle passes 

 through the following stages: 

 Adult, egg^ larva, and pupa. It 

 usually produces only 1 generation 

 a year, and spends all but about 3 

 months in the soil. 



Adults begin emerging from the 

 soil in early May and continue to 

 do so until early fall, the exact time 

 of emergence depending on the lo- 

 cality. They are dark gray, are 

 about % 6 inch long, and have a 

 white fringe, or band, along the 

 outer edges of the body. They 

 feed on margins of leaves for sev- 

 eral days and then begin laying- 

 eggs. All adults are females and 

 are capable of laying fertile eggs. 



The eggs are laid in masses in the 

 soil (usually near the roots of a 

 plant), or at the point of contact 

 between soil and objects such as 

 sticks, gravel, plant stems, and other 

 things lying on or protruding from 

 the soil. They are covered with a 

 sticky substance that hardens upon 

 drying and holds them together and 

 also to the object on which they are 

 deposited. 



An egg mass usually contains 11 

 to 14 eggs, but some masses have up 

 to 60 eggs. Each egg is about % 5 

 inch long. 



How many eggs an adult lays and 

 how fast she lays them depend upon 

 the kind of plant on which she feeds. 

 In tests conducted by entomologists 

 at Florala, Ala., beetles that fed on 

 peanut foliage laid an average of 

 1,600 eggs (one beetle laid 3,258 

 eggs) , but those that feci on grasses 

 laid an average of only 4 eggs. 

 Legumes and broad-leaved plants, 

 such as cocklebur, ragweed, pea- 

 nuts, soybeans, and strawberries, in- 

 duce heavy egg laying; while cow- 

 peas, blackberry, lespedeza, Mexi- 

 can clover, pecan, and tobacco have 

 the opposite effect. 



Adults live 2 to 5 months, and lay 

 eggs much of that time in the pres- 

 ence of favored foods. 



The right combination of temper- 



ature and moisture is required for 

 the eggs to hatch. Eggs laid during 

 the summer usually hatch in about 

 17 days. But those laid during the 

 fall and winter require longer peri- 

 ods — sometimes as much as 100 

 days. Some eggs may remain viable 

 throughout the winter and hatch 

 the following spring. 



The larvae are yellowish- white 

 grubs that are up to y 2 inch long. 

 They enter the soil and feed almost 

 constantly. As they grow, they 

 molt, or shed their skins, several 

 times. It usually takes about 11 

 months for the larvae to develop, 

 but under certain conditions some 

 larvae require 2 years or more. 



Normally, these insects pass the 

 winter as larvae in the soil, but they 

 may overwinter as eggs. In the 

 spring and summer, the larvae con- 

 struct cells 2 to 6 inches below the 

 soil surface where they transform 

 into pupae. In about 13 days, the 

 adults emerge. 



CONTROL 



Cultural control. — Farmers can 

 suppress heavy white-fringed beetle 

 infestations and prevent the pest 

 from becoming numerous by fol- 

 lowing certain cropping systems. 

 These measures vary with the crops 

 grown and rotations practicable in 

 different areas. The general prin- 

 ciples of cultural control is the rota- 

 tion of crops favored by the beetle, 

 such as peanuts, soybeans, and vel- 

 vetbeans, with crops that are un- 

 favorable to it, such as pasture 

 grasses, small grains, and corn. 

 Corn should be planted solid not 

 inter-cropped with legumes. Fa- 

 vored host crops should not be 

 grown more often than once in 

 every two or three years on the same 

 land. Plants with fibrous root sys- 

 tems do not suffer as heavy damage 

 by the larvae as those having tap- 

 roots. The addition of organic 

 matter to the soil also causes a re- 

 duction in damage by white-fringed 

 beetle larvae, one of the most eco- 



