INSECT PESTS 



49 1 



paraffin oil or tobacco water into the gallery by means of a small syringe with a fine 

 nozzle, and immediately closing the hole with a plug of well-kneaded clay ; or a piece of 

 tow soaked in tar or paraffin oil may be pushed as far as possible into the tunnel, and 

 the opening closed with clay so as to keep the smell in as much as possible. Currant 

 bushes are sometimes attacked by the caterpillars of the Currant clear-wing moth (Sesia 

 tipuliformis) , which bore into the branches and shoots of Currant bushes, causing the 

 death of the branch. The best way to deal with this insect is to cut off the shoot below 

 where the caterpillar is and burn it, as the branch would die in any case. Among the 

 insects that are injurious in their perfect state perhaps the various kinds of weevils are 

 the most troublesome. The Pea and Bean weevils (Sitones lineatus] are often very de- 

 structive to our Pea and Bean crops ; they injure the young plants by eating the leaves, 

 gnawing large notches in them. They are difficult pests to deal with, for they only feed 



FIG. 63. American Blight in various stages. | signifies natural size, 

 i. The fly. 2. The insect. 3. Showing its effect upon a fruit-tree shoot. 



at night, and are so much the colour of the soil that it is almost impossible to find them 

 when they drop off the plants, which they do at the least alarm. Dusting the leaves 

 when they are wet with powdered lime, or soot, or gas-lime and soot mixed together, or 

 spraying with paraffin emulsion is useful in preventing the weevils from attacking the 

 leaves. Sand soaked in paraffin oil strewed on each side of the rows is also useful ; the 

 young plants should be pushed into rapid growth as quickly as possible. The well- 

 known grubs in Nuts are the progeny of the Nut weevil (Balaninus nucum) ; the Black 

 Vine weevil (Otiorhyncus sulcatus), and its brother, the clay-coloured weevil (O. picipes), 

 are both very injurious to the foliage of plants in greenhouses, particularly to Vines, 

 Peaches, Roses, Ferns, and many plants grown for their foliage, and their grubs feed on 

 the roots of these plants. Out of doors they injure Raspberry bushes by feeding on the 

 leaves, and by eating right through the young shoots. These beetles only feed at night, 

 and, like the Pea weevils, fall to the ground on being in any way disturbed ; they may be 

 caught in houses by laying white sheets under the plants before it is dark, and afterwards 

 throwing a bright light on them and shaking or tapping them. Out of doors an open 



