INSECT PESTS AND THEIR CONTROL 971 



Clover Mite (Bryobia prcetensis, Garm.). — A common red mite on 

 many plants, including clover, alfalfa and a number of varieties of fruit. 



Treatment.- — Dust the plants with sulphur and lime at rate of 1-4, or 

 spray with either 10 per cent kerosene emulsion or sulphur in water, 1 

 pound to 4 gallons. Destroy eggs on fruit trees in winter with 20 per cent 

 kerosene emulsion or with lime-sulphur. 



Bur. Ent. Cir. 158. 



Clover Root Borer (Hylastinus obscurus, Marsham). — The beetle win- 

 ters over in clover roots; emerges 

 in the spring and lays eggs in 

 the larger roots. The grubs, on 

 hatching, bore through central 

 part, destroying plants. 



Treatment. — Plow the fields 

 after haying, allowing the roots 

 to dry. Pasturing checks the 

 injury. Infested field should not 

 be allowed to stand over the sec- 

 ond season. 



Bur. Ent. Cir. 119. 



Corn Ear Worm (Heliothis 

 obsoleta, Fab.). — This insect is 

 also known as the cotton boll 

 worm, the tobacco bud worm or 

 the tomato fruit worm. It has 

 a long list of other food plants, 

 but on many causes no serious 

 injury. On corn the eggs are 

 laid by the moths upon the silk. 

 The larvse upon hatching enter 

 the ear and begin to feed on 

 the immature grains. Cotton is 

 not seriously attacked until the 

 corn silks are drying up, as corn 

 is much preferred by the worms. 

 The adults lay their eggs upon the 

 cotton leaves and the larva;, after feeding for a short time upon the foliage, 

 enter the bolls. They attack tobacco by eating into the buds, and tomatoes 

 are injured by attacks upon the fruit. 



Treatment. — For all crops the injury is materially lessened by late 

 fall plowing and cultivation which crushes many pupae in the soil and 

 exposes others to the winter. On cotton the insect may be well controlled 

 by two applications of an arsenical dust or spray at the time the eggs are 

 hatching. Tobacco may be protected by dropping into the buds a little 



iBur. Ent. Cir. 158. 



Clover Mite (Bryobia proelensis) . l 

 Enlarged; natural size shown by line at right. 



