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Walkingsticks belong to the grasshopper order, Orthoptera and the Phasmatidae family. These highly unusual and strange looking insects blend so well with the host plants that they feed on, that they are rarely noticed. They are very long, thin and vary in color from brown to green, sometimes mottled with shades of grey or red and essentially wingless, except for one species in Florida. If they lose part of a leg, they have the ability to partially regenerate or replace it during their next molting. They are very slow moving and will remain motionless for long periods of time. In the urban environment, one does not have to be too concerned with their feeding, since walkingsticks are primarily forest defoliators, but they can be a problem in small towns near large forests. They will feed on apple, aspen, birch, dogwood, hackberry, hickory and locust, but prefer basswood, oak and wild cherry. Eggs are oval, black or brown with an olive-colored band on one side and are laid in the Fall. The female will drop from 1-3 eggs per day from high up in the tree, which drop to the litter on the forest floor, where they overwinter. Eggs hatch in early June, the nymphs first feed on under story plants before moving higher up into the crown of the trees. In the north, there is 1 generation every 2 years, while in the southern part of their range there is generally 1 generation per year.
Wasps are generally not garden pests and the few that are destructive are far out numbered by the beneficial types. They are included here because one particular garden species Vespa crabro germana, the European hornet, can be quite destructive to various trees and shrubs. This is the largest hornet in the United States, 1" long, dark reddish brown with orange markings on the abdomen, it resembles the well known cicada killer wasp, but is hairier, stouter and lacks the terrifying ovipositer (stinger). This hornet injures plants not by feeding on foliage but from chewing and tearing off the bark from twigs and branches, which it uses to build its nests. The resultant damage to the plant is severe girdling of the branches, which often looks as if the damage had been done by a larger animal like a squirrel (which often gets the blame for it.) Injury is most common in August and September when large colonies of hornets have developed. Lilac seems to be a favorite, but other plants can be troubled include birch, boxwood, franklinia, mountain-ash, poplar, occasionally rhododendron, willow and several other trees and shrubs. European hornets can be found along the Alantic seaboard from Massachusetts to Georgia. They have also been reported in Ohio and Pennsylvania. Other species of wasps can also be destructive in the garden, some may cause galls to form on leaves in which the larvae or other stages of the insect are passed and some injure fruit by eating large holes in it.
Webworms are caterpillars that feed on a host plant protected by a web. Some webworms have been given common names such as the tent caterpillar, but they are still considered a webworm. Others are known with webworm in the name. There are various species of webworms some more common than others and they can be found on trees, shrubs, field crops/vegetables and even grass. Some of the more common ones are the barberry webworm, cotoneaster webworm, fall webworm, garden webworm, juniper webworm, mimosa webworm, oak webworm, pine webworm and the sod webworm that can trouble lawns.
Weevils are beetles, from the order Coleoptera, with a head prolonged forward and downward, which looks like a snout or beak, with mouth parts at the end, similar to the curculios. They can be one of two types, those that feed on stored seed or those that feed on ornamental plants. Most species of weevils can be found in the family, Curculionidae and are destructive plant feeders. Weevils that that attack fruits and nuts are called curculios (see curculios).
Whiteflies are minute sucking insects with powdery white wings that resemble tiny white moths. They are often found feeding on the underside of leaves in great numbers and when disturbed fly out in clouds. Primarily tropical insects, they can be found in abundant numbers in greenhouses or indoors on house plants throughout North America. In the summer months they can be found on some garden plants in the north, but in southern states like California, Florida and the Gulf states they may be active all year. The life history is quite the same for most species of whiteflies. Eggs only 1/100" are laid and attached to the underside of the leaves by short stalks, hatching in 4-12 days into active yellow crawlers, they move about avoiding strong light, then insert their beaks and begin to feed. After several growth stages, the nymphs rest in a pupa stage before emerging as an adult. A complete life cycle will require 20-30 days at room temperature and there are several overlapping generations per year continuing all winter in greenhouses and in warm climates. For control yellow sticky traps can be used. Malathion or insecticidal soap is recommended for control.
Wireworms are the larvae of the click beetle. For those of you who are not sure what a click beetle is, they are a slender, hard shelled beetle, generally brownish-gray to black in color and about ½" - 1" long. What is so unique about this beetle and how it gets its name, is the fact that when it falls or is placed on its back, it will throw itself several inches into the air creating a sharp clicking sound as it tries to right itself. If it lands right side up, it will scurry away quickly, if it doesn't it will keep trying until it does, since the beetle cannot roll over without popping up into the air. The beetle will feed on leaves and flowers, but will not cause much injury. Wireworms (the larvae) are smooth, shiny, dark yellow to reddish-brown, about 1"-1/2" long and are entirely soil feeding insects, feeding on underground plant parts such as seeds, roots, tubers, bulbs, etc. They can be found throughout North America, and most of the world, and can be quite destructive to crops of the grass family, but will also trouble root crops, vegetables and flowers. Damage can be noticed by wilting, stunting or even complete death of the plant. Click beetles (the adults), overwinter in the soil and emerge in the spring to lay their eggs, the wireworms will hatch in 3-10 days and will remain in this larval stage from 2-6 years feeding Spring through Fall, then moving deeper into the soil to overwinter. During the first year, the wireworm will feed little and will not cause much injury. Normal feeding of underground plant parts will begin in the second year. When ready to pupate in late summer, they change to a white pupae, make a small cell, 3-8" below the soil surface, and pupate for the winter. The pupa will change to an adult in about 3 weeks, but will not emerge from the ground until early spring. Do to the variable number of years a larvae may live before pupation to an adult, there will always be wireworms of all ages and sizes present in the soil at any given time. There are various species of wireworms, but all are similar in the damage they do. To control wireworms, soil should be cultivated thoroughly to a depth of at least 8" every week for about a month in the fall, to destroy the overwintering cells. Parasitic nematodes can also be applied to the soil. |
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Webworms - 
Whiteflies -