PECAN PESTS 



1671 



Howard it feeds upon 120 different species 

 of forest trees, ornamental trees and fruit 

 trees. Tlie fall web worm is widely dis- 

 tributed, being found all over the eastern 

 and central parts of the United States, 

 and as far west as Texas and Montana. 



Adults 



The adult insect is a beautiful, delicate 

 moth with wings expanding an inch or an 

 inch and an eighth. 



Jfatnral Enemies 

 Mantis 



Among the best friends of the fruit 

 growers and general agriculturist are the 

 insects variously known as the "devil 

 horses," "mule-killers," and "praying 

 mantes." The eggs are laid in large white 

 masses usually stuck to branches of trees. 

 The "devil horses" live upon the cater- 

 pillars of the web worm and destroy num- 

 bers of them. 



Wheel Bng 



This is another common insect that 

 preys upon the web worm caterpillars. 

 The wheel bug is so called because of the 

 toothed prominence on its back that re- 

 sembles half a cog-wheel. The larvae, 

 which are bright red, and the adults are 

 all carnivorous and destroy even more of 

 the web worms than the devil horses. 



Stink Bngs 



These bugs are familiar to most of us 

 because of their unpleasant odor. This 

 is especially noticeable, sometimes, upon 

 berries, for these bugs leave a strong 

 trail wherever they travel. One of these, 

 known as Podisus spmosus^ preys upon 

 the web worm and should be carefully 

 protected. 



An Egg Parasite 



Although the eggs of the web worm 

 moth are very small, there are some in- 

 sects small enough to live within the eggs 

 and devour the contents. In some cases, 

 whole batches of eggs have been found 

 parasitized by this tiny insect. The name 

 of this small but efficient parasite is 

 Telenomus Mfidus. 



Parasites on the Caterpillars 



There are also a few small insects that 

 are parasitic on the caterpillars. These 



insects deposit their eggs on the caterpil- 

 lars and the larvae live within the cater- 

 pillars, eventually killing them. 



Eemedies 



Owing to the fact that the caterpillars 

 feed in groups, they may be easily reached 

 and destroyed with considerable efficiency. 

 Perhaps the most effective remedy for 

 this insect in small pecan orchards or 

 where a small number of trees is con- 

 cerned is to destroy the caterpillars by 

 burning them when they have collected 

 together within their webs. This may be 

 done by any efficient form of torch fast- 

 ened to the end of a long pole. A bundle 

 of rags or a porous brick saturated with 

 kerosene oil and wired to a pole is as 

 good as any. Care should be taken not to 

 burn more of the foliage than is neces- 

 sary. During the fall and winter months 

 the cocoons of the web worm may be col- 

 lected in quantities and destroyed. Fin- 

 ally, there are the arsenical poisons. 



Hickory Shnck Worm 



GraphoUtJia caryana 

 Sometimes pecan nuts are attacked, as 

 they approach maturity, by a small white 

 caterpillar, which mines its way through 

 the shucks of the nuts. This caterpillar 

 is the hickory shuck worm, the larva 

 of a small moth. 



But little is known of its life history, 

 and, until more is known of its habits, the 

 best advice that can be given is to gather 

 and destroy the infested nuts by burn- 

 ing them. 



Pecan Leaf Caterpillar 



Datana angusii G-. & R. 

 Datana integemma G. & R. 

 Perhaps the most serious enemies of 

 bearing pecan trees are the two species 

 of insects named above. They are better 

 known than most of the other pests. Both 

 of these caterpillars are very much alike 

 In appearance and very likely both of 

 them are taken for one and the same in- 

 sect. Prof. H. A. Morgan reports the 

 second one named as occurring in 

 abundance on pecans in Louisiana. From 

 our observations we believe the species 

 angusii to be most abundant in Missis- 

 sippi. 



