164 Pecan-Growing 



Teche, and Young. Among those showing a high degree of 

 susceptibility are Capitol, VanDeman, Schley, Stuart, Nel- 

 son, Frotscher, Taylor, Alley, Appomattox, and Delmas. 



Control, 



Natural enemies of the leaf case-bearer are helpful 

 toward its control. In addition to a few species of minute 

 parasitic wasps, flies, and predacious bugs attacking this pecan 

 enemy, certain birds, including the mocking-bird, blue jay, 

 and orchard oriole, have been known to peck open the cases 

 and eat out the larvae. 



The best method of control is to spray the trees thoroughly 

 with arsenate of lead between the middle of August and the 

 last , of September. All efforts to destroy this species by 

 spraying with arsenical mixtures during the spring and with 

 concentrated lime-sulfur and miscible oils in winter have 

 thus far failed. The cases or hibernacula seem to be so 

 durable and tightly woven that winter sprays fail to pene- 

 trate them to an effective degree. Spraying with arsenate 

 of lead in the spring seems to fail largely because a sufficient 

 percentage of the larvge is not exposed to the poison at any 

 one time to make an application worth while. 



The spray mixture recommended for the August or Sep- 

 tember application is as follows : 



Arsenate of lead powder 1 pound 



Lime (unslaked) , 3 pounds 



Water 50 gallons 



The lime is slaked with water, the mixture diluted to ten 

 or twelve gallons, and strained through a fine-meshed 

 strainer so that no particle large enough to clog the spray 

 nozzle will escape into the solution. The arsenate of lead is 



