82 STATE POMOLOGICAL SOCIETY. 



on a tree attacked by canker worms, and soon falls to the ground. 

 No insect may be more easily controlled than the canker worm 

 by the use of arsenical sprays. The banding of large street trees 

 with tree ink or tar is often very effective. For orchard trees, 

 however, it would be cheaper to spray. 



Cherry and pear trees frequently suffer from the attacks of 

 the so-called pear slug, a slimy insect larva that consumes the 

 soft parts of the leaves in the early summer months. When 

 these insects are full grown they descend to the groimd and 

 emerge as four-winged saw-flies about mid-summer. These 

 latter insects give rise to a second brood which does not com- 

 plete its transformations until the following spring. The 

 destruction of the first brood should be the chief object aimed at 

 and as soon as the slugs are abundant on the trees, they should 

 be treated to a thorough spraying with arsenate of lead. In the 

 case of the second brood it may not be desirable to use arsenical 

 poisons because of the size of the fruit and at this time the insects 

 may be destroyed by the use of kerosene emulsion. 



Of the scale insects common in our orchards, but three species 

 are particularly injurious. The oyster-shell bark louse and 

 scurfy bark louse have similar habits and are seldom injurious 

 except to young trees. With both species the young lice hatch 

 in the early summer from eggs which are secreted beneath the 

 female scale and swarm over the trees. When they have found 

 a suitable spot on the bark, their slender beaks are inserted into 

 the tissues and* feeding on the sap, they soon secrete shell-like 

 coverings. The sexes mature in the fall and the females, after 

 fertilization, deposit large numbers of eggs beneath their scales. 

 They may be destroyed by spraying or washing the infested 

 trees in the winter with whale oil soap, used at the rate of two 

 pounds to one gallon of water. They are more easily killed by 

 spraving with kerosene emulsion in the spring at the time when 

 the young lice are hatching and swarming over the trees. 



The San Jose scale, a comparatively new insect to the eastern 

 United States, does not readily yield to remedial measures and is 

 one of the most dangerous of all fruit tree pests. It is possible 

 that you have had no experience with it as yet in Alaine, but it 

 hardly seems probable that you will entirely escape from it. It 

 was first noticed about 1870 in California and from its damage 



