CHERRY AND PEAR SAWFLY. 57 



and Pear; but it is mentioned by Mr. P. Cameron that "the 

 damage done by these ugly brutes to fruit trees is very often 

 immense ; especially is this the ease during very dry seasons. 

 They are found on most species of Pyrus, Prunus, Cerasus, 

 Ruhus, and Amygdalus, as well as Cratcegus, Qaercus, and 

 Betula:'* 



Prevention and Remedies. — The slugworm attack can be 

 checked by dusting or syringing. The caterpillars, if annoyed 

 by throwing a caustic powder on them, such as quicklime or 

 gas-lime, can throw it off at first by exuding a coating of 

 slime, and thus, as it were, moulting off the obnoxious matter; 

 but they cannot keep on continuing this process ; therefore a 

 second application of the powder (of course soon after the 

 first) takes effect and kills them. If a good time is allowed 

 to elapse between the dressings, they will have regained the 

 power to produce the slime exudation, and the dressing will 

 do little good. 



Heavy syringings of the tree with strong soapsuds, applied 

 by a powerful garden-engine, are very effective in getting rid 

 of this pest. Tobacco-water will destroy them ; and lime- 

 water has also been found useful, in the proportion of a peck 

 of lime to thirty gallons of water ; it is noted that if two 

 pounds of soft-soap are added, it will improve the mixture. 



The sawiiies have been found to fall to the ground on the 

 tree being shaken, and to remain for a short time motionless ; 

 consequently it would be a good plan to place boards covered 

 with wet tar, or cloths, beneath the trees, and shake the flies 

 down on them early in the morning or late in the evening 

 (or at whatever time it was found they were collected on the 

 leafage), taking care that they were destroyed before they 

 could escape. 



The recurrence of the attack, which, when once established, 

 is a very common circumstance, may be prevented by skim- 

 ming off the surface of the ground and removing the cocoons. 

 These may lie below the surface at from one to about four 

 inches deep, according to the state of soil. If the earth is 

 stirred over by a competent observer, little balls, probably 

 much resembling the colour of the earth they are in, will be 

 found, and may at once be identified by just tearing the spun 

 case open, when the caterpillar or, later on, the chrysalis 

 will be found within. When once the observer has found 

 how deep these cocoons lie, it is easy to have the surface-soil 

 removed to just below that depth, and by removing this and 

 destroying it, ivith the cocoons tvithin it, the infestation may 



* See 'British Phytophagous Hynienoptera,' by P. Cameron, vol. i. p. 225. 



