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SOME NUT INSECTS OF IMPORTANCE IN MARYLAND 



\ By Ernest N. Cory, State Entomologist, College Park, Md. 



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Thei .-e are a great many insects that attack nut trees, their foliage 

 and the nu^ts themselves, in this state, but for the most part their ac- 

 tivities are d(!^^.cidedly sporadic and not of enough consequence to warrant 

 special control measures. However, there are a few insects that seem to 

 be pretty generally distrib.^ted over the state, and that appear each year 

 in some portion of the nuat growing territory. I have limited the 

 number of insects that I will', discuss to six that might be considered 

 as major pests. Enough is know^n with regard to the life history and 

 habits of these six pests so that we ^^an give you a schedule of control 

 operations that should give a fair degree- of protection to your plant- 

 ings. 



Black walnuts, Persian walnuts, pecans anul chestnuts are the nuts 

 that have been planted generally in Maryland. Of course, there are 

 large quantities of native black walnuts, white walnuts or butter- 

 nuts, several varieties of hickories, chinquapin and ha,_zel nuts which, in 

 general, complicate the control of the insect pests. Certain sprays 

 and grove practices, however, if followed with regulari'ty^ will control 

 the major pests. 



Insects that Injure the Buds 

 Two pests, requiring attention early in the season, injure the new 

 growth, and if not controlled will continue to injure the foliage 

 throughout the season. They are the Pecan Shoot Bore'r, Acrohasis 

 caryae Grote, and the Pecan Bud Moth, Proteopteryx hoilUana Sling. 

 Either of these pests is capable of so retarding the growth of the pecan 

 and Persian walnut as to make a difference of many years jn the bear- 

 ing age and a stunting of the tree that is anything but desir,able. 



The Pecan Shoot Borer 

 This insect starts its injury when the buds are just T^eginning to 

 unfold. The fleshy leaf stems at the terminals are bored I ,y the larvae 

 starting at a point some distance above the attachment. The larvae 

 generally work their way downward and the leaf withei-g and dies. 

 The point of entrance is usually marked by a conspicuous mas., of black 



