NURSERY AND ORCHARD INSECT PESTS 5 



young orchard scatter tobacco stems or tobacco dust about the base of the 

 young trees and work it into the soil. On the large bearing trees this may 

 also be done but it is especially important to young trees free from the louse. 



Insect Pests of the Trunk and Limbs 



In this group are included some of the most vital pests of apple; such as 

 the borers and scale insects. 



Round-headed Borer (Saperda Candida). This pest works just at the 

 surface of the ground, throwing out of its tunnel sawdust-like cuttings. It is 

 worse on neglected bearing trees in the orchard but also at times may appear 

 on older apple trees in the nursery. It requires three years to complete its de- 

 velopment from egg to adult. When full fed the fleshy, whitish grub or borer is 

 an inch long and as large around as a pencil. The tunneling and girdling work 

 weakens the tree and permits rot to set in. 



CONTROL. In the nursery make sure that nearby old trees are not serving 

 as breeding places causing infestation on the nursery trees. Also avoid carry- 

 ing over scion trees or other unused trees until they become sources of infesta- 

 tion. 



In the orchard cultivate about the trunks of the trees to keep down grass 

 and other rubbish as it seems to attract or protect the pest. Also go over the 

 trees in the fall and in the spring and carefully dig out, or destroy with a wire, 

 borers where present. During the early summer months keep the base of the 

 trunks painted with whitewash to which enough lime-sulphur solution is added 

 to give a distinct odor. In Arkansas asphalt paint applied, at the temperature 

 of about 115 degrees Centigrade, to trees four years old or older gave good 

 results. Where possible it is cheaper and better to prevent infestation thru 

 proper orchard management than to clean up the orchard once the trees are 

 infested. 



Flat-headed Borer (Chrysobothris femorata). This pest is smaller than 

 the round-headed borer and confines its work to the bark and growing layer of 

 trunk and limbs. It is common on nursery trees and also in orchards. As a 

 rule it works where mechanical injury, sunscald or canker is at work on a 

 tree. The grub or borer is whitish in color and has the segments of the thorax 

 expanded so as to appear to have an enlarged head which gives it. its common 

 name. It completes its life cycle in one year. It is not confined to the apple 

 tree, which makes it all the more difficult to control. 



CONTROL. During the early part of summer examine trees for signs of 

 injury on trunk or larger limbs. If present carefully remove borers, disinfect 

 wounds and paint over patches. As a precaution keep nursery and orchard as 

 far from woods as possible and eliminate old worthless apple trees as well as 

 haws and other trees from the vicinity of the orchard. 



Shot-hole Borer (Scolytus rugulosus). This small beetle and its tiny 

 grub may attack all kinds of fruit trees and other trees. It is most important 

 in the orchard but on weakened nursery trees it may also appear. The female 

 beetle makes a tunnel between the bark and wood and lays eggs along either side 

 of this. In time the small borers extend their work, often girdling limbs or the 

 trunks of small trees, causing weakening or death of such trees. As a rule it 

 is a weakened tree that is most likely to suffer injury. 



