Everyone has experienced a plant pest. It could be on your houseplants, your backyard garden, or your indoor growroom. PG's approach to eliminating infestations relies on biological control

Biological control : A term used to describe the use of natural organisms to reduce the effects of undesirable organisms (pests) and to favor desirable organisms such as crops, trees, animals, beneficial organisms or insects.
via beneficial insects and safe non-toxic measures, such as neem oil or pyrethrums, that ensure no harmful materials are utilized on your ingestables or in your living environments.

Dealing with pest infestations in an indoor environment or enclosed area, such as a greenhouse, is an entirely different animal relative to an outdoor environment. In an outdoor scenarioit is much easier to create the necessary trophic levels for

Trophic level : A group of organisms that occupy the same position in a food chain.
balance and good production via plant placement and choice, but in an enclosed space the disruption of this balance is as easy as a new house plant from a nursery or a hanger-on spider mite hitching a ride on your clothing. Indoors there is no possibility of a predator flying by looking for a meal without you bringing it into the scenario, so it is the responsibility of the gardener to implement procedures or products that can create this balance

upon affliction. Attention should be paid to plants being brought inside for the winter or to be re-potted and to soils being re-used or transferred indoors because these things can be infested with pests and do not want to be brought into an indoor scenario. Attention should also be paid to products used to fight pests, such as pyrethrums, that may leave a residual that results in a negative impact on introduced beneficials. Most pest controls are not pest specific.

In a commercial operation growers routinely introduce pests and their predators to create balance so as to preempt any catastrophic infestation. It is up to the individual grower if this is to be done on a personal level. Having said that, it is a hoop that every indoor gardener will more than likely jump through eventually. It happens to the best of us! The good news is that there are effective tools to use for control. Be diligent and inspect your plants regularly using some type of magnifier if possible.

Spider Mites

The Spider Mite is the most common and the persistent pest around. Most people do not notice them until they are firmly established and producing webs. Bottom line, they are good at what they do. It is always best to inspect your plants on a routine basis. Spider Mites hang out underneath your leaves. They are tiny, oval shaped mites, about the size of a pinhead and lay perfectly round eggs at random that are clear to amber in color. There are a number of beneficial insects available that can adequately control and even eliminate Spider Mites. The trick is getting
to the eggs. There is no spray that will adequately kill the eggs, so the only true means of eliminating an infestation is by beneficial insects. However, plants can live with Spider Mites and sprays can keep them at bay to the point that they do not affect yields. Adult females have the ability to go dormant for months at a time, then re-emerge to lay more eggs so the lackadaisical gardener will be sure to have a constant battle on their hands, especially indoors, if attention is not maintained upon infestation.
Whiteflies
Another common pest, Whiteflies are evident on top and underneath the leaf surface and quickly flutter up when disturbed. All stages of Whiteflies suck plant juices. What finally kills the plant infested with Whiteflies is not usually the Whiteflies themselves, but a black sooty mold that grows on their accumulated honeydew excretions. The excretion is very apparent upon leaf inspection and can actually prevent photosynthesis by blocking chlorophyll . A leaf wash is beneficial in this case, but can be counterproductive to creating balance with beneficials by killing the beneficials themselves. Any kind of pest soap, or dish
soap for that matter, can be toxic to insects. If a leaf wash is used be extra careful by washing each individual leaf separately and carefully as opposed to drenching the plant as a whole for coverage. This will prevent premature death via the materials used and from washing them off of the plant altogether.

Aphids

Aphids are another common and familiar garden pest. They come in almost every color- green, yellow, pink, brown, black, or any shade in between. The surefire way to diagnose an Aphid infestation is to use a magnifier to find the pair of tiny "dual exhaust pipes" on their posteriors. These are properly called cornicles and Aphids are the only insects that have them.

They also produce honeydew that can potentially be fatal, so a leaf wash is prudent. They also carry plant diseases; so quick and effective control is a good idea. Beneficials are very effective at Aphid control.

Generally adult Aphids are wingless, but most species also occur in winged forms, especially when populations are high or during spring and fall. The ability to produce winged individuals provides the pest with a way to disperse to other plants when the quality of the food source deteriorates.

Although they may be found singly, Aphids often feed in dense groups on leaves or stems. Unlike leafhoppers, plant bugs, and certain other insects that might be confused with them, most Aphids do not move rapidly when disturbed.

Thrips

About 1/10" long, Thrips can move quite quickly for their size. Larvae and adults look similar, but adults have wings and can fly. They feed by scraping and rasping at the leaves leaving them paper-thin with severe infestations. They are usually noticed by a silvery metallic looking sheen covering the leaf or little black specs, which are thrip fecal matter. Thrips move down into the soil or growing media to pupate. At
this stage they can be treated with Predator Nematodes. Nematodes should gain control after several months, but for severe infestation we recommend using Nematodes in conjunction with above-ground control with a quality garden spray or beneficial insects. Winged adults are attracted to the color blue, so some blue sticky traps or some garden goo and construction paper make an effective control for adults.

Fungus Gnats

Fungus Gnats are easily recognized flying aimlessly as if they are drunk amongst your plants. They also have an uncanny ability to find your orifices making them a traditional indoor garden pain. They thrive in moist environements by way of a larval stage that pupates in the root zone. While the adult stage is not harmful to plant life, the larval stage is extremely harmful on root development resulting in spots on leaves, brittle old growth, and overall stress. While these garden pests are not hard too eliminate most people do not realize that the life cycle goes through the root zone causing the grower to believe the problem is taken care of when they see no more drunken flyers. In reality, the larval form is underway

producing the next generation of flyer.

Focus should be on eliminating both forms- a double edged sword of sorts. Treating only the larvae leaves the adults to re-infest, and treating just the adults leaves the larvae to molt again. Long-term control is often attained using beneficial insects or some form of Bacillus thuringiensis (Bt). Bt creates plague in the larval stage of insects and is extremely effective in eliminating a fungus gnat infestation.

Fleas

Anyone with animals, and many without, experience flea infestations. You won't get good results by putting Predator Nematodes on your pets, but by applying them to the soil in areas of your yard where pets frequent will greatly reduce Flea populations. For pet control try Diatomaceous Earth, which can also be used in your lawn and carpets and especially in places your pets might sleep, is very effective at controlling and eliminating flea infestation. DE is a natural, completely non-toxic soft bodied pest control and can be rubbed into pet fur. It is even used in stock feed to kill intestinal worms, so it can be used with confidence around the house.

Mealybugs

 Clusters of Mealybugs look like a cottony mass. It's only on close examination that they're seen to be individual, soft bodied, very slow moving insects. They normally accumulate at a crotch or joint and breed somewhat slower than other insects with each generation taking about a month. But they can gradually build up to quite dense and damaging populations. There are very effective beneficial insect controls for mealybug infestation.

Scales

Scales resemble little oyster shells on stems and leaves. Many, but not all, species produce shiny honeydew on leaf surfaces where a leaf wash would be beneficial. Active only as babies, Scales soon lose their legs, grow a hard outer shell, and settle in for a quiet life of sucking plant juices. Scale control with predators alone has been variable, so the best defense against adults is peeling them off individually with your fingernail or scissors.

Fly species

 Nobody likes flies. There are fly parasites available that can effectively control over abundant flies. They are best utilized when there is a known source of fly pupae production, such as a stable, compost pile, or waste buildup.

Ants

Ants in your garden don't damage your plants directly, but they are so fond of the sweet honeydew produced by Scales, Mealybugs, and especially Aphids, that they actually herd them from plant to plant to encourage greater honeydew production. They also defend their captive herds against natural predators you introduce, so it's important to control Ants where hired bugs are being used. Diatomaceous Earth is an extremely effective totally natural and non-toxic means of controlling ants. DE works by physically scratching and dehydrating ants as opposed to using chemicals. DE is also an effective Fire Ant controller.

Japanese Beetles

Japanese Beetles are destructive lawn pests, and a nuisance as well, especially east of the Mississippi River. Milky Spore is the bacteria Bacillus popilliae and works directly on Japanese Beetle grubs. Complete control can be expected after as little as one application and can last for up to ten years or longer! For more immediate control Predator Nematodes can be used.

Caterpillars

 If you have chunks chewed out of your leaves or you notice piles of fecal matter scattered, look closely and you'll probably detect worm-like larvae slowly crawling around. Corn Earworm, Cabbage Looper, Tomato Hornworm, and other such pests are all offspring of various moths and butterflies, and they can be controlled with a form of Bacillus thurigenesis mentioned above in the fungus gnat discussion. The larval stage of the pest must ingest Bt for it to be effective so ensure uniform coverage of foliage for the quickest and most effective results.

If you want to ask a specific question regarding pest identification or control contact PG or your local extension service.

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