224 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



nate of lead, 1 pound to 10 gallons of water, just as they are 

 set, has been found to afford very satisfactory protection in 

 Connecticut. 



The Tobacco Stalk-worm * 



Professor W. G. Johnson found this species, also known as 

 the Corn-root Webworm, to be a serious pest to growing tobacco- 

 plants in southern Maryland, where it seems to have been a 

 tobacco pest for at least fifteen years, and it has also been noted 

 in Delaware. 



The Injury. The injury to tobacco is described by Professor 

 Johnson as follows: " The uninjured tobacco had a leaf -spread 

 of from ten to twelve inches. A few rods beyond, where the soil 

 was not so gravelly and better, we found the larvae had literally 

 destroyed the first and second plantings, and were at work upon 

 the third, damaging it severely, although the ground had been 

 replanted before the last planting. Here and there was a young 

 plant just beginning to wilt, and invariably we found the larva at 

 work cither in the stalk or at the base of the plant just below the 

 surface of the ground. So far as I could ascertain the attack is 

 always at the surface or just below. In many instances the 

 larvae had hollowed out the stalks from the base of the roots to 

 the branches of the first leaves. Many plants were gnawed 

 irregularly around the stalk below the surface, and some, in fact, 

 were completely cut off at the surface, the insect always working 

 from below. In the great majority of cases the larvae were found 

 in a small mass of web near the plant, and sometimes within 

 it. In one plant, less than six inches high, we found four larvae 

 within the stalk, but as a rule only a single one was present." 



Professor Johnson concluded " (1) that it is most likely to 

 occur over local areas in tobacco following timothy or grass; 

 (2) that the character of the soil has little or nothing to do 

 with its ravages; (3) that the attack upon corn is also a frequent 

 occurrence in the same section; especially when following grass 

 or timothy." 



* Crambus caliginosellus Clem. Family Crambidce. See p. 161 and 

 Bull. 20, n. s., Div. Ent., U. S. Dcpt. Agr., pp. 99-101, 1899. 



