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Maggots are the larvae of flies and like the larvae of other insects, feed on the fruits of various plants. Just as with other insect species, there are many kinds of maggots, some feed on plant fruits, some feed on dead and decaying animals. Some common plants affected by maggots are apple, blueberry, cherries, plums, cane fruits, cabbage and other vegetables.
Mantids, otherwise known as the 'preying' or 'praying' mantis are members of the grasshopper order (Orthoptera) and are usually considered beneficial insects because they prey upon other insects. Unfortunately, the mantis doesn't know the difference between those insects that are beneficial to the garden and those that cause problems, so they are just as likely to eat the good as well as the bad ones. Many of us may be familiar with this insect, as its common name refers to the way it sits in a prayer-like stance, waiting for its unwary prey; or is it the fact that they prey on their victims with their long, muscular legs, fitted with grooves and spines for grabbing and holding. Full grown mantis are not afraid to strike at prey much larger than themselves. Young mantis look similar to the adults, except for their wings, and likewise eat other insects, sometimes starting with each other, for they are cannibals from the first day they are born. The mantis appears in mid-summer, but rarely do we notice them since they blend well into the surroundings of the landscape, and look like just another twig on a plant. Eggs over winter in rounded masses of a hardened frothy substance about an 1' or so in diameter that is tannish-brown in color. These nests are attached to tall grasses or to the twigs and small branches of shrubs and are made up of a series of chambers for 100 or more eggs. If you notice these overwintering egg masses on plants, do not destroy them. If you don't like where momma mantid put her next summers arrivals, simply cut off the branch, with the nest attached, and relocate them to another shrub in the garden and tie the branch on. If you accidentally cut off one of these thinking it was some kind of deformity on your plant, you obviously made a mistake, but now you know. There are about 20 species known throughout North America.
Mealybugs are relatives of scale insects and are actually soft scale insects with small, oval, segmented bodies covered with a white powdery wax. There are two types, long-tailed mealybugs are those that produce living young called crawlers and have long, waxy, filaments at the end of the body and short-tailed mealybugs which reproduce by eggs and lack the longer tails. Most species are found in the southern United States and all species are found in greenhouses. The long-tailed mealybug is widely found in greenhouses and outdoors in warm climates. In the north, most species are indoor or greenhouse pests, however the Comstock and Taxus mealybugs can overwinter as far north as New York and Connecticut. Mealybugs can infest all plant parts, feeder roots, root crowns, branches, leaves, flowers and fruit. The long-tail feeds on new shoots and leaves and have a wide range of host plants on which they feed. Ants sometimes help in distributing mealybugs from one plant to the next since they are also attracted to the honeydew excretions left by the mealybug. Damage to plants is caused by both the adults and the nymphs by the sucking of plant juices which results in discolored, deformed and wilted foliage and the eventual death of the affected plant parts. The honeydew excretions left on the plant parts also supports the growth of sooty mold fungus. Mealybugs can be controlled biologically with parasitic wasps.
Midges are small, two winged insects related to the fly and are often referred to as gnats. The biting midges are often encountered when one goes into the woods, but the Gall midges or Gall gnats are those that the gardener and the plants needs to be concerned with. Many of the galls found on trees and shrubs are caused by midges. Some common plants affected by midges are apple, catalpa, chrysanthemum, dogwood, grape, honeylocust, juniper, Monteray pine, pear, rhododendron, rose and spruce.
Mites are not true insects, but belong to the animal class Arachnida, order Acarina, which includes spiders, scorpions, harvestmen (daddy longlegs) and ticks which differ mainly from insects in having four instead of three pair of legs. Young mites only have three pair of legs, but add a fourth pair at maturity. Eriophyidae members or those referred to as Gall or Blister mites only have two pair of legs. Mites are very small, almost microscopic in size. They can be injurious to humans, animals and to plants, but some species are beneficial like the Amblyseius cucumeris, a beneficial, predatory mite that feeds on injurious plant pests such as spider mites and thrips. Of the various kinds of mites, many infest living plants and live by sucking juices from the foliage and/or flower buds. There are Gall mites which cause galls to occur on plants, Rust mites which cause the foliage and fruit to take on a rust colored appearance and spider mites which cause the foliage to yellow or become off color. Plants will become weakened, stunted and leaves may also drop if infestations become severe. Of the various species of mites, the two most widely known and troublesome in the garden are the Spruce spider mite which affect evergreens such as arborvitae, hemlock, juniper and of course spruce, and the Two-spotted spider mite, commonly referred to as red spider mite which is commonly found in every garden, attacking a variety of plants both inside and outside.
Moths belong to the insect order Lepidoptera and have wings that are covered with scales. Moths differ from butterflies in that they are mostly night fliers, and have a large, heavy, hairy abdomen, antennae that may be feathery, but not knobbed, wings often with two eye-spots and that lie horizontally when at rest and a pupae that is often protected by a cocoon. Moths are only injurious to plants in their larval or caterpillar stage and are usually harmless, except for the fact that more moths, lay more eggs, and in return bring about more caterpillars. Some of the larval stages (caterpillars) of moths are commonly known by their adult 'moth' name such as the Buck moth, Codling moth, European Pine Shoot moth, Gypsy moth, White-marked Tussock moth and various others.
Nematodes are not insects, but microscopic animals, worm-like or threadlike in form. Listed here because a very large number are recognized as plant parasites. Some are also parasites of animals and others are predaceous on other nematodes or fungi. They live in moist soil, water, decaying organic matter and in the tissue of other living organisms. Some are pathogenic, causing disease in humans, animals and plants, others prey upon pathogenic forms and are therefore beneficial, while some parasitic nematode species are used as a biological control for root weevils, crown and stem borers, corn rootworms and lawn insects. Parasitic plant nematodes are rarely over a millimeter long and are hardly visible with the naked eye. They are cylindrical in shape, usually tapered at both ends, transparent or with a whitish or yellowish tint. They lack a true head, but they do have a mouth that is surrounded with sensory organs. Behind the mouth is a stoma, then the esophagus, the intestine and then the rectum. There are no specialized organs of circulation or respiration. Nematodes puncture the tissues of the host plant or animal prey with a hollow spear-like organ or stylet imbedded within their mouth, then inject a secretion from its salivary gland that predigests the food before they suck the juices in through the stylet, by means of a bulbous apparatus or muscular swelling at the end of the esophagus. Plant nematodes can be sedentary or migratory. They move through the soil by threshing about, but may only move short distances, about 30" or so a year. Most long range movement is done by external means, tools, feet, irrigation water or shipment of infested plants and soil. Plant parasitic nematodes can infest roots, stems, bulbs, leaves and buds. Plants affected by nematodes generally become stunted and decline. Some nematodes such as the Root Knot nematode cause galls to form on the roots of plants. Control for nematodes can include crop rotation and other cultural practices or planting a nematode suppressing cover crop such as marigolds. Chemical fumigants can be used, but these are developed for use and treatment on fallow soils. Greenhouse soils can be steam sterilized. |
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Mantids - 
Mealybugs -