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Galveston Monthly

Bugs & Slugs

Aug 03, 2019 12:47PM
When working in the garden, we are acutely aware of the presence of bugs and the question of whether they are the good guys that we need to maintain a healthy garden, or are they the bad guys that are about to devour and destroy what we have worked so hard to create. The following insects are certainly not inclusive of all that may be found in any landscape but are a few examples of each sort.

The Detrimentals
Aphids are tiny soft-bodied insects that cluster on leaves, flowers and stems of plants. Aphids may cause distorted, curled, or yellowing leaves and malformed blooms. Black sooty mold is often associated with the presence of aphids as they secrete undigested fluid called honeydew.
Aphids are extremely prolific, and the population increases rapidly in the summer months.

Whiteflies are tiny white insects that are found on the undersides of leaves where both the larvae and the adult insects suck sap from the leaves. The above-mentioned problem of sooty mold is also associated with this pest.

A sure indication that whiteflies are present is when the plant is moved or shaken; the insects can be seen fluttering rapidly around it.

Slugs and Snails cause silvery trails that wind along the plants and leaves. They are mollusks, relatives of oysters and clams and work mainly at night to protect their soft bodies from the sunlight.

Spider Mites are related to spiders. However, they are not beneficial insects but a common garden pest that causes widespread damage while having the advantage of being difficult to spot. About the size of pepper grains, they cause damage by sucking the sap from the undersides of leaves. Place a white paper under a leaf and tap the plant—if specks drop to the paper and begin to crawl around you have spider mites. Unfortunately for island gardens, spider mites thrive in hot dry weather.

 Leaf Miners are particularly partial to fruit trees. Light colored trails can be seen through the leaves that will eventually curl, dry up and die. Adult leaf miner flies lay their eggs on the leaves; the hatchlings penetrate the leaf to feed on the plant tissue between the inner and outer
layer of the leaf.

Mealy Bugs appear on stems and leaves as white cottonylooking clusters. The effected leaves may be sticky and covered with black sooty mold from honeydew. The young mealy bugs are mobile and will spread rapidly to nearby plants if not eliminated quickly.

The Beneficials
Beneficial is defined as promoting a favorable result. The beneficial insects listed here will aid in promoting a favorable result in your garden daily, simply by the existence of their voracious appetites. As they work their way around and over your plants, they are controlling the
infestation of the undesirables. Most people are familiar with their names and can readily identify them, but educating others, particularly youngsters, is important to maintain a continuing source of these garden helpers without risking extermination with the excessive use of pesticides and insecticides.

Ladybugs are one of the most recognizable beneficial insects. They are fond of aphids, scales, mites, and other soft-bodied insects. A ladybug can eat up to 50 aphids a day and up to 5000 aphids in its lifetime that may be as short as four weeks. Ladybugs are small, oval-shaped
winged insects, usually red with black spots or black with red spots.

Lacewing adults feed on nectar but the lacewing larvae enjoy aphids, small caterpillars, whiteflies, and thrips. The tiny larva is called the “aphid lion” because of its insatiable
appetite. It attacks its prey, injecting a paralyzing venom then draws out the body fluids of its victim.

Praying Mantis prefer flies, bees, crickets, and moths and will eat only live insects. They are green or tan, useful hues for camouflage among plants. Praying Mantis have six jointed legs, a three-part body (head, thorax, and abdomen), two antennae, large eyes, and a hard
exoskeleton. Mantis can rotate their triangular-shaped head in nearly a full circle. Most adult mantis are two to six inches long and females are larger than males.

Assassin Bugs kill many garden pests including flies, mosquitoes, beetles, and large caterpillars. Assassin bugs lie in wait for insects then attack quickly to paralyze their prey by injecting a toxin that dissolves tissue and then sucking up the other bug’s tissues. They have an elongated
head with a distinct narrow neck and long legs. Most species are dark in color with splashes of brown, red, or orange.

Dragonflies and Damselflies seek out mosquitoes, gnats, and other flying insects, hovering in mid-air and catching them while flying. The dragonfly has a three-part body, two large eyes that take up most of the head, three pairs of jointed legs, and two pairs of long, delicate,
membranous wings. Damselflies are similar to dragonflies, but the wings of most damselflies are held alongside and parallel to the body when at rest. 

Allies & Enemies
Friends and foes of the garden are ever-present; thus, it is important not to eliminate the allies via an uninformed attack on the enemies. Rather than a blanketed see-and destroy mission at the first sight of a garden pest, use a rational approach - identify the pest, assess the damage, and apply the least toxic solution. Use chemicals with caution, and always seek out a natural
solution to doing away with the detrimental varieties. For example, smaller insects like aphids can be removed simply with a strong jet of water.

Large numbers of beneficial insects can usually be found in areas or on plants with high populations of harmful insects like aphids, so it is also crucial to deal with individual pest populations as specifically as possible. When the “bad guys” are gone, the “good guys” will leave
as well.