(see Fig. 2, h) somewhat resemljle in miniature those of a hen and are de- 

 posited in irregular masses, usually concealed l)eneath pieces of loose bark and 

 similar objects. They hatch about the time that the apple tree unfolds its leaves 

 in the spring, the date varying with the locality and season, from the middle of 

 April to the latter part of May. The young canker-worms eat greedily and grow 

 rapidly, usually attaining their full size in from three to four weeks from the time 

 of issuing from the eggs. They then enter the ground to a depth of from two to 

 five inches, according to the character of the soil ; here each one forms a small 

 cell, which it lines with a few strands of silk, and shortly afterward transforms to 

 the chrysalis, in which condition it remains until the following winter or early 

 spring, when the change to the adult insect takes place. 

 Only one generation is produced each year. 



NATURAL EXEMIES. 



Large numliers of canker-worms normally fall a prey to various kinds of birds 

 and several kinds of beetles feed upon them. Certain kinds of wasps provision 

 their nests with them to serve as food for their young. Ichneumon flies and 

 Tachina flies while in the larva state also destroy many by feeding upon them 

 internally. The eggs are desti-oyed by mites, and a minute Chalcis fly preys upon 

 them, each egg serving as food for one of the flies. All these checks to the undue 

 increase of the canker-worms when present in any given locality usually succeed 

 in keeping them within due limits, but when these are absent, or the weather 

 conditions are unusually favorable to the increase of the worms, artificial means 

 will be found necessary to keep them in subjection. 



REMEDIES AND TREVENTIVE MEASURES. 



Owing to tlie fact that it is only in exceptional years that canker-worms appear 

 in destructive numl)ers, but little attention is usually paid to them until the 

 blighted appearance of the infested trees proclaims their presence to the orchard- 

 ist. At such times the damage is already well under way and will be increased 

 somewhat before an insecticide can take effect. As an immediate partial remedy 

 the jarring method may be emploj'ed. This consists in first jslacing a strip of stiff 

 paper around the trunk of the tree, and smearing it with some kind of sticky sub- 

 stance, such as tar, printers' ink, thick molasses, or bird lime, to prevent the worms 

 from again ascending. Tbe tree is then jarred or shaken, causing some of the larvte 

 to drop to tlie ground, while others let themselves down by silken threads, which 

 must be severed by means of a cane or stick, to prevent the worms from reascend- 

 ing the tree. 



A general si)raying witharsenicals as soon as the worms appear will riil the trees 

 of these pests in a very short time. Paris green is the more satisfactory of the 

 arsenicals, as it is less liable to injure the foliage than London purple, and its use 

 has proven safe and effective at the rate of one pound to 150 gallons of water. 

 Before mixing the Paris green with water it is advisable to add an equal weight of 

 freshly slaked lime, mixing thorougldy. The lime takes up any free arsenic, and 

 prevents jiossible injury to the foliage. During the process of applying the poison 

 which can ) )e best accomplished by means of an ordinary spray pump and nozzle, 

 the solution should be kept constantly stirred to j^revent the poison from settling 

 to the bottom. The worms are most readily poisoned when newly hatched, and 

 it is therefore very important to spray as soon as the young worms first appear, 

 with the object also of preventing the damage which would result from delay. 



After the worms have assumed the chrysalis form just beneath the surface of 

 the ground, large numbers may be destroyed by plinving and harrowing the 

 orchard. This may be done at any time during August or the first half of Sep- 

 tember. 



