NURSERY AND ORCHARD INSECT PESTS 



13 



trol the pest. It attacks various evergreens, shades and ornamental shrubs 

 worse, as a rule, than apple trees. 



Leaf-roller (Archips argyrospila). This small caterpillar is often very 

 destructive to foliage of nursery trees and occasionally to bearing apple trees. 

 It may have three or four broods a year in this state and when abundant the 

 small yellowish millers are conspicuous about the nursery or orchard trees. 

 The small active caterpillars roll or fold the leaves on which they feed. It may 

 also feed to some extent on the fruit, especially around the blossom or stem 

 end or where two fruits touch. 



CONTROL. In the nursery arsenical sprays applied just as the broods of 

 young worms begin their work has proven entirely effective in one of the larger 

 nurseries in the state. The development of the pest should be carefuly fol- 

 lowed and the spray applied before the young worms fold or curl the leaves 

 too much. In the orchard the regular summer applications of poison sprays, will 

 control any ordinary outbreak of the pest. The pest passes the winter in the 

 egg stage. The eggs are deposited on limbs or twigs in small circular light 

 patches. Some have used oil emulsion sprays to destroy the winter eggs with 

 fair results while others find them ineffective. 



Leaf-crumpler (Mineola indigenella). The leaf-crumpler is one of the 

 most common foliage feeding caterpillars on young trees in the orchard or 

 nursery. The caterpillar is a small reddish or brownish colored caterpillar 

 which prepares, and lives within, a 

 slender, coiled case. The case is 

 usually attached to a twig and has 

 one or more leaves attached to it. It 

 passes the winter as a half grown cat- 

 erpillar and transforms to the adult 

 early the next summer. It feeds on 

 the foliage of other trees, fruits and 

 haws. 



CONTROL. It is most abundant 

 on small trees and in the fall or win- 

 ter when the leaves are off the trees 

 it is an easy matter to see and re- 

 move by hand the winter cases con- 

 taining the small caterpillars. An 

 arsenical spray applied soon after 

 the foliage appears in the spring is 

 also effective. In the nursery this is 

 the most practical remedy. In the 

 bearing orchard the regular summer 

 arsenical sprays control this as well 

 as other common foliage-feeding 

 caterpillars. 



Leaf-miners (,$>/>.). There are a number of small caterpillars which 

 live and develop within the cellular structure of the leaf. The serpentine, 

 blotch, trumpet and tentiform leaf-miners are the most common ones found 

 in the foliage of apple trees. Besides these the pistal and cigar case-bearers and 



FIG. 15. lyCaf-crumpler: a, Tube with larva 

 head protruding; b, cluster of tubes; c r 

 head of larva, enlarged; d, moth, enlarged 



