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Horntails, found in the family Siricidae (true horntails) are called wood wasps and those found in the family Cephidae, are called stem sawflies. True horntails are a inch or more long and get their common name from the horn-like tail at the end of their abdomen. The females are cylindrical in shape and thick wasted with a long, horn-like ovipositor that looks much like a stinger. They insert this ovipositor deeply into the wood of newly felled, injured or dying trees to deposit their eggs. The yellowish-white larvae bore in solid wood without any outside opening, as they begin to feed they pack the boring sawdust behind them. Pupal cells are made near the surface of the wood and when they have matured to an adult they cut emergence holes to the surface. Horntails can be found from coast to coast, primarily in the northern parts of the United States, they are more common in the west, being partial to western conifers. One of the more commonly found horntails is the Pigeon Tremex, considered a borer and often found listed under borers. The larvae of this specie will attack apple, beech, elm, hickory, maple, oak, pear and sycamore. The Raspberry Horntail (a western species) causes damage to the young shoots of blackberry, loganberry, raspberry and roses. The Rose Stem Sawfly (an eastern species) causes damage to roses.
Hornworms are large caterpillars with a pointed projection at the end of their body that resembles a horn. They are the larvae of sphinx moths, family Sphingidae, and can generally be found feeding voraciously on tobacco, tomato, eggplant, potato, groundcherry and related weeds. The sphinx moth is sometimes referred to as the hawk or humming-bird moth, often seen in gardens at dusk feeding on nectar from deep-throated flowers. It is the larvae of this beautiful moth that is injurious to plants. The female sphinx moth lays greenish-yellow eggs, singly on the underside of leaves. The young larvae, generally green in color hatch within a week. They will feed for about 3-4 weeks and when fully grown are about 3" long. They will molt 5 times, then pupate 3-4" deep into the soil. In the north, there is 1 generation per year, while in the south there may be 2 or more generations per year. Picking hornworms off by hand is generally sufficient enough control for the small garden. Bacillus thuringiensis (BT), is a biological bacterium that is recommended for control. Note: Take notice of the Hornworm caterpillar before you destroy them. If the caterpillars are covered with oval white objects attached to the skin by one end, do not kill the caterpillar. They are the cocoons of the parasitic (and beneficial) braconid wasp. The female wasp lays her eggs inside the body of the hornworn, when the larvae hatch, they feed for a while inside the caterpillar before moving outside to spin cocoons on the body of the hornworm. If left alone, these parasitic wasps will emerge to feed on other hornworms. Almost seems sadistic, but this is natures way.
Katydids, related to grasshoppers, are some of the most common insects known and can be found throughout most of the United States, but they are rare in the northernmost states. Arboreal in habit, they are seldom found on the ground. Katydids blend well within their host plants, their green bodies provide excellent camouflage and their wings often look like leaves. The males are those that do the singing by rubbing their front wings together, and each species has a characteristic song. Generally not much damage is caused by the katydid, their feeding damage is often limited to chewed out semi-circular holes along the leaf margins, but they have been known to defoliate young citrus trees and other ornamental plants. Control is generally not necessary. |
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Horntails - 