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ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



the writer has seen the entire fruit crop 

 ruined by the larvae, and the trees com- 

 pletely defoliated so that not a green leaf 

 could be noticed. When trees are so de- 

 foliated it is hardly possible for them to 

 produce fruit buds for the following sea- 

 son. 



Distribution 



The fruit tree leaf roller is generally 

 distributed throughout the United States. 

 Stedman, in Bulletin No. 71 of the Mis- 

 souri Experiment Station, page 7. states 

 that "this insect is found in damaging 

 numbers practically all over the United 

 States from Maine to the Gulf and west- 

 ward to the Pacific coast and up as far as 

 Oregon." 



Food Plants 



The insect is a very general feeder 

 and consequently has been reported on a 

 large number of plants. It appears at 

 times in injurious numbers on apple, 

 pear, plum, cherry, apricot, quince, peach, 

 rose, currant, raspberry and gooseberry. 



Character of Injury 



As the manner in which the larvae at- 

 tack the various host plants differs to a 

 certain degree, it seems advisable to give 

 a rather full discussion of the more im- 

 portant injuries, especially those occur- 

 ring on fruit trees. 



In the spring, just as the buds are 

 bursting, the larvae begin to gnaw their 

 way out of the eggshells and hard pro- 

 tective covering of the egg masses. The 

 young caterpillars at once migrate to the 

 developing buds and begin feeding on the 

 unfolding leaves. At first they eat small 

 inconspicuous holes in the unfolded 

 leaves, and at this time the average or- 

 chardist is not aware of their presence. 

 After feeding in this manner for a few 

 days the larvae become quite conspicu- 

 ous as they begin to spin fine silken 

 threads from leaf to leaf. Eventually 

 they fold or roll up a single leaf or a 

 cluster of leaves and here they feed for 

 the greater part of the time, though 

 occasionally straying out of their conceal- 

 ment to feed in the open. Before the 

 blossoms are fully out, or even before the 

 cluster buds have separated, the "worms" 



can be observed webbing them together 

 and feeding voraciously. Very often seri- 

 ous injury results before the trees come 

 into blossom. Later in the season the 

 webs produced by the larvae are often 

 quite conspicuous. 



As soon as the young fruit has set the 

 larvae cease feeding on the foliage to 

 a large extent, and now fasten one or 

 more leaves to the fruit and within this 

 protection feed greedily, at first eating 

 the skin only, but shortly consuming the 

 pulp and the seeds or stone, depending 

 on the kind of fruit attacked. Some- 

 times young apples are completely de- 

 voured except for the stem and a portion 

 of the calyx end. Cases have been 

 noticed where the larvae have complete- 

 ly gnawed through the stems, thus caus- 

 ing the fruit to fall to the ground or re- 

 main suspended within the feeding nest. 

 Damage done to apples as well as other 

 fruits is usually so severe that the fruit 

 can not outgrow the injury, thus caus- 

 ing a large percentage of unmerchantable 

 or second-class fruit at picking time. 

 Much fruit is also caused to fall prema- 

 turely on account of the serious injury 

 inflicted on it when young. 



Life Habits 

 The Egg 



The female moth deposits her eggs in 

 compact oval clusters of about twenty- 

 five to more than one hundred, anywhere 

 upon the bark of the fruit trees that serve 

 as its food supply. As soon as the egg 

 mass has been deposited, the female moth 

 smears the eggs over with an impervious 

 material which is thrown out from the 

 extremity of the abdomen, and which pro- 

 tects the eggs from the inclemencies of 

 the weather and the attacks of predace- 

 ous Insects for nearly ten months, or un- 

 til the buds begin to open the following 

 year. So there is but one brood of the 

 worms each summer. 



The eggs are stuck so tightly to the 

 bark when they are deposited that they 

 often remain for several years. The old 

 egg patches are readily recognized by the 

 numerous small punctures from which the 

 larvae or worms escaped. 



