184 Pecan-Growing 



There is a great variation in the susceptibility of vareties 

 of pecans to scab. Some are practically immune, others are so 

 susceptible that practically the entire crop is lost when they 

 are planted in a region with little elevation and near the 

 coast. Susceptible varieties near the coast may be highly re- 

 sistant when grown further inland; the reverse is true when 

 varieties are transferred from inland to coast regions. Some 

 of the varieties that have been planted on the coastal plains of 

 the southeastern states may be grouped as follows, according 

 to their susceptibility or resistance to scab : Very susceptible, 

 Delmas, Georgia, and San Saba; partially susceptible and 

 sometimes severely attacked, Bolton, Pabst, Schley, and Van 

 Deman; usually free of disease but occasionally attacked, 

 Alley, Mobile, Moore, and Nelson. Those practically immune 

 are Frotscher, Moneymaker, Russell, Stuart, Success, and 

 Teche. During periods of frequent rains and hea^^ dews the 

 varieties having considerable resistance are likely to be se- 

 verely attacked, and very susceptible kinds may be destroyed 

 entirely. 



Cont7^oL 



The propagation of varieties of pecans immune or 

 highly resistant to scab is one of the most satisfactory 

 and surest means of control. Susceptible varieties may be 

 top-worked with cions from highly resistant or immune 

 trees. 



Spraying the trees with bordeaux mixture will be effective 

 in holding the scab in check, provided the varieties are not 

 unusually susceptible. The following proportions are satis- 

 factory : 



