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on a long pole. Asbestos fibre soaked in kerosene and placed in a tin can 

 nailed to the end of a pole makes an excellent torch. The flame should 

 be passed below the nest so as to destroy it and the contained caterpillars, 

 care being taken not to injure the bark of the branches, a rather difficult 

 operation. The nests should, of course, be destroyed while the caterpillars 

 are within them. The clusters of the Forest Tent Caterpillar may be 

 removed when they are massed on the lower branches or trunks of the 

 trees by means of a torch or by brushing them off with a stiff wire brush, 

 or they may be killed by a strong spray of kerosene emulsion applied 

 directly to the caterpillars. 



Gathering Cocoons. — After the caterpillar stage is past and the 

 cocoons are spun, the latter may be gathered and thus the escape of the 

 moths which emerge will be prevented. The collected cocoons should 

 be placed in a box covered with a coarse wire netting, about three-six- 

 teenths of an inch mesh. This will allow the useful parasites to escape 

 but retain the moths, which may be destroyed later. 



Spraying. — When spraying apparatus is available the simplest and 

 most convenient method is the application of Paris green in the proportion 

 of one pound to 160 gallons of water, or lead arsenate, two pounds to 40 

 gallons of water, to the infested trees or parts of trees, as the caterpillars 

 are appearing from the eggs. Orchards which receive the regular poison 

 sprays for the codling moth and the plum curculio rarely suffer from tent 

 caterpillars. The young caterpillars are killed by the poison before they 

 are able to do much damage. After they are more than half grown it is 

 much more dilificult to kill them by arsenical preparations; and they should, 

 therefore, always be attended to early in the season. \\'hen it is necessary 

 to spray specially for these pests, it is usually sufficient to apply the 

 mixture to the foliage on the particular branches which are attacked. 

 Lead arsenate is perhaps to be preferred on account of its adhering qualities. 



The Black Walnut Caterpillar, Datana integerrima, is sometimes 

 abundant on black walnut, butternuts and other deciduous trees. The 

 caterpillars are black when full-grown, covered with long white hairs, and 

 become about two inches in length. They feed in large groups and some- 

 times cause considerable defoliation. They are easily controlled by spray- 

 ing the infested branches with lead arsenate or Paris green. 



The Golden Oak Scale, A sterol ecaniiim variolosum, is an important 

 enemy of cultivated oaks. It appears as a small yellow scale insect, round 

 and strongly convex, often densely coating the twigs. The insects suck 

 the sap and when numerous seriously weaken the trees. The young 



