I0 8o THE BOOK OF GARDENING. 



do not feed alike, and what therefore would be fatal to one would 

 be quite harmless to another. 



Let us take, for example, two of the commonest pests known 

 to the fruit-gardener— Greenfly (Aphides) and the caterpillars of 

 the abundant Gooseberry Moth (Abraxas grossulariata). The 

 first is a sucking insect, the second a chewing one. Now, though 

 the caterpillar may readily be controlled by systematically poisoning 

 its food-plant, the Aphides would not be in the least affected, say, 

 by covering the plants in which they were found with a solution 

 of Paris -Green or powdered hellebore, both of which are virulent 

 poisons. This may be readily accounted for when the method 

 of feeding adopted by the two insects is known. The Aphides 

 derive their sustenance from th.e juices of the leaves, and before 

 they commence to "suck" they first penetrate the poison-area 

 with their beak-like mouth. 



Then there are the borers— wood-feeding insects, say like the 

 Currant Shoot Moth, whose larvae feed on the shoots ; the Com- 

 mon Goat Moth Caterpillars, which tunnel the trunks of many trees ; 

 or the lesser-known Wood Leopard Moth Caterpillars, which are 

 found in the branches. Obviously these are without the reach of 

 insecticides ; so also are, after a time, those insects which enter 

 the immature flowers and fruits, or feed between the leaf-surfaces 

 like the leaf-miners. 



Yet another section embraces such root-feeders like Grape Phyl- 

 loxera ; American Blight (in part) ; the troublesome Cabbage Gall 

 Weevil, whose wart-like excrescences are only too well known to 

 the vegetable cultivator ; the much-dreaded Eelworms, so plentiful 

 at the roots of grasses used as composts ; and those omnivorous 

 depredators the Wireworms. All of these call for special 

 treatment. Trapping may be resorted to in the case of some, 

 baking the soil in that of others, while alternate cropping in the 

 case of Cabbages and such like will prove beneficial by freeing 

 the soil of the objectionable animals. 



Then there are a lot of very destructive insects — Moth-Cater- 

 pillars, certain Aphides, and Beetles which are leaf-twisters, or 

 it may be case-makers, and though they feed upon the green 

 parts of the plants, they are protected by the curled or twisted 

 leaves, in which they feed comparatively secure from insecticides. 

 Certain scales, again, are difficult to deal with because the exuded 

 matter forming the outer covering of the pests is insoluble in 

 anything which might with safety be employed. 



While it is very desirable that all animal pests should be kept 

 . at bay, yet the crops which best pay for attention are fruit and 

 vegetables, the former especially. The difference in price obtain- 

 able on the market between that which has been protected 

 against insect and other pests and that which has been allowed 

 to take its chance is so great as to be incredible. Even with 

 crops which are required for home consumption, appearances 



