The Garden Under Glass

304 THE GARDEN UNDER GLASS pick out all those straw-coloured grubs which will do so much damage if allowed to remain. Wasps.—These are a great nuisance in a vinery, where they will quickly spoil many bunches of grapes. The best method of keeping them from the grapes is to tack tiffany over the ventilators. Failing this, I would advise the trapping of the wasps, the destruction of the nests and the setting about the house of jam pots partly filled with sweetened beer. One of the finest preventive measures is to catch the queen wasps during May. A good time to search for the nests is about midday, when the wasps are more likely to be travelling backwards and forwards. River banks and dry ditches are likely places for nests. When found, mark the nests and destroy them at the first opportunity with cyanide of potassium. A shillings worth may be dissolved in a quart of warm water, It is a deadly poison and should be labelled and kept in a safe place. Put some cotton wool in the solution and keep it tight. Use a pointed stick and with it put a piece of saturated cotton wool in the hole of the nest. After a few hours it should be possible to dig out the nest and destroy the comb. A can of water should be at hand, and when the nest is reached water should be poured in and the comb broken and mixed with the earth. White-fly.—Has already been dealt with under Greenfly. Wood-lice.—Often called also sow bugs and slaters. These are very destructive in a greenhouse. Use boiling water to kill them in their haunts and search for them among any rubbish near the hot-water pipes. They have a partiality for decayed wood, and if some flat pieces be placed on the ground there are almost sure to be some found beneath it, and can then be destroyed.