8. _Wasps_, after a dry spring, may be very numerous. Their nests often hold many thousands. Large numbers may be destroyed thus: place a hand-light upon bricks, make a small hole in the top of this, and over it put a sound and closely-fitting one. Fruit cut open should be thrown beneath the lower light. The wasps often go up through the hole, and do not return. Their buzzing attracts others. Destroy by burning sulphur beneath, or by drowning. A glass destroyer on a similar principle is sold in china-shops. Open-mouthed bottles filled with beer sweetened or water sweetened with treacle will lure many to destruction. Queen wasps in spring and wasp-nests must be noticed and destroyed. Fasten a piece of cloth soaked in a solution of cyanide of potassium (a small quantity dissolved in hot water), and put it in the nest; all the wasps will be killed. Dig out the grubs. This is a deadly poison, and should be handled only by an expert. The emanation from the solution must not be breathed. Tar does almost as well. A nest may be partly dug and flooded at night. A clean wine bottle (half-filled with water) inserted in the place of the nest (the top of the neck level with the surface of the ground) will probably capture all stragglers. Some make a heap of injured fruit and syringe the wasps with nicotine soap, eight ounces to a gallon of hot or cold water. This plan kills quickly, but the fruit no longer attracts. Squibs a half-inch in diameter, three inches long, made of gunpowder moistened with water, one-fourth of flowers of sulphur added, mixed into a paste, wrapped in brown paper, and tied at one end, are good for the work. After dark, light the squib, push the lighted end into the hole, put a sod over, and ram it in to confine the fumes. In a few minutes dig up and destroy the grubs, then fill up the hole. If the nest is high up, attach the squib to a stick, light, and keep it close (while burning) to the entrance. Young gardeners enjoy this squibbing process. [Illustration: FAN-SHAPED PEAR TREE, ONE YEAR AFTER GRAFTING, SHOWING THE LENGTH OF RESULTING SHOOTS] THINNING FRUIT If you wish for fine fruit or a crop every year, trees must not be overworked, especially in their earlier days. Thin whenever there is a large crop, but do not begin too soon, as some fruits are not fully fertilised, and may fall. Never let fruits touch each other. As the fruits mature, give any grub-eaten to the pigs, and use inferior pears for cooking purposes. Grub-eaten fruit must not lie on the ground. SUMMER, WINTER, BRANCH AND ROOT PRUNING; LIFTING