Treatment. - Bordeaux mixture applied liberally is the best remedy, — it drives them away.
Four-striped Plant-bug (Paecilocapsus lineatus). - A bright yellow, black-striped bug about one-third of an inch long, puncturing the young leaves and shoots of many plants.
Treatment. - Jarring at any time of day into a dish of dilute kerosene. Kerosene emulsion (diluted five times) when the bugs are young, in their nymphal stage. Cut off and burn the tips of the growing shoots in early spring to destroy the eggs.
Galls. - See Nematode Root-gall, below.
Gipsy-moth (Porthetria dispar). - Larva, nearly two inches long when mature, very hairy, nearly black, with a yellow stripe along back and sides. Devours many kinds of foliage. Confined to New England, where it was introduced from Europe about 1869. It has become a serious pest.
Treatment. — Spray with arsenate of lead as soon as the caterpillars hatch in the spring. Band trees with tanglefoot.
May-beetle or May-bug (Lachnosterna fusca). — A large and familiar brown beetle, feeding upon the leaves of many kinds of trees.
The common white grub is the larval state. It often does great damage to sod and to strawberries. Sometimes called June-bug.
Remedies. — See under Corn, p 314.
Mealy-bug (Pseudococcus citri and P. longifilis). — A white, scale-like insect, attacking greenhouse plants.
Treatment. — Whale-oil soap. Carbolic acid and soap. Removing insects with brush on tender plants. House-plants may be washed in soapsuds. The best procedure in greenhouses is to knock them off with the hose. A small, hard stream of water upsets their domestic affairs.
Nematode Root-gall (Heterodera radicicola). — A disease characterized by the knotting and contortion of the roots of the peach, orange, and many other plants. The knots are mostly rather soft swellings, and on the smaller roots. It is usually most destructive on the peach. It is caused by a nematode, or true worm (not an insect). Gulf States. Attacks greenhouse plants in the North. Preventive. - Plant non-infested plants in fresh soil ; bud into healthy stocks. Fertilize highly, particularly with potassic fertilizers. Set the trees 8 or 10 inches deep in high and dry soils. Infested small trees may be remedied, in part at least, by transplanting them into highly manured holes which have been prepared contiguous to them. Does not live in regions where the ground freezes deeply. If it is feared in greenhouses, see that the soil has been thoroughly frozen before it is used. Whitewash the benches.
Red-spider or mite (Tetranychus bimaculatus). - A small mite infesting many plants, both in the greenhouse and out of doors. It flourishes in dry atmospheres, and on the under sides of the leaves. In some forms it is reddish, but usually light-colored and two-spotted. Common.
Remedies. - Persistent syringing with water will generally destroy them, if the spray is applied to the under surface. Use lots of force and little water to avoid drenching the beds. Sulfur and water. Dry sulfur. Sulphocide.
San Jose Scale (Aspidiotus perniciosus).—This scale is nearly circular in outline and about the size of a pin-head. When abundant it forms a crust on the branches, and causes small red spots on the fruit. It multiplies with marvelous rapidity, there being three or four broods annually, and each mother scale may give birth to several hundred young. The young are born alive, and breeding continues until late autumn, when all stages are killed by the cold weather, except the tiny, half-grown, black scales, many of which hibernate safely. Spray thoroughly in the fall after the leaves drop, or early in the spring before growth begins, with lime-sulfur wash, or miscible oil, 1 gallon in 10 gallons of water. When badly infested, make two applications, one in the fall and another in the spring. In case of large, old trees, 25 per cent crude oil emulsion should be applied just as the buds are swelling.
Scale-insects. — Various species of small insects inhabiting the young growth of trees, and sometimes the fruit, in one stage characterized by a stationary scale-like appearance. Lime-sulfur and miscible oils are the best remedies. Species which migrate on to the young growth in spring can be readily dispatched at that time by kerosene emulsion.
Snails. - These animals are often very troublesome in greenhouses, eating many plants voraciously.
Preventives. - Trap them by placing pieces of turnip, cabbage, or potatoes about the house. Scatter bits of camphor-gum about the plants. Strew a line of salt along the edges of the bed. Lime dusted about the plants will keep them away.
White ants or termites. - These insects often infest orchard trees in the southern states, particularly in orchards which contain old stumps or rubbish.
Remedy. - The soap-and-arsenites wash brushed over the trunk and branches of the tree.
Wire-worm (various species). - Slim and brown larvae, feeding upon the roots of various plants. They are the larvae of the click-beetle, or snapping-beetle.
Remedy. - Arsenicals sprinkled upon baits of fresh clover or other material which is placed about the field under blocks or boards. Sweetened corn-meal dough also makes a good bait. The best treatment is to plow infested land early in the fall. A system of short rotations of crops will lessen injury from wire-worms.