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Maintaining your yard

Identifying Pest Problems
Scout the yard for pests. Inspecting plants for pests helps identify problems early, before they get out of hand. Common plant pests in this area include aphids, mealybugs, scales, whiteflies, thrips, spider mites and caterpillars. Detecting small insects and mites can be difficult; life cycles as short as one week add to the problem.

To detect small pests, strike the leaves of small branches against a sheet of white paper and use a ten-power (10X) magnifying glass. Scales and whitefly larvae attach to the plant. Look for them on branches and the undersides of leaves.

Sooty mold on foliage is a good indicator of infestation by insect pests that pierce the plant and suck sap. These insects often secrete a sugary product known as honeydew. This substance encourages the growth of black fungi which appear as sooty mold.

Ants are another good indicator of the presence of pest insects as they feed on honeydew and care for insects that produce it.

Extensive plant damage with few pests may signal the decline of a pest population. Beneficial insects may already be doing the job for you. These may include lady beetles (commonly called lady bugs), lacewings and parasitic wasps.

Tolerate some insect damage and leaf disease on plants. No one can maintain an insect- and disease-free landscape, and a little damage won't hurt your plants. Remember, to have the "good guys" there must be some "bad guys" as a food source.

If a pest problem persists, take a sample of the offending insect to the University of Florida Extension Service for identification and IPM treatment suggestions.

Controlling Pest Problems
Handpicking, pruning or spraying with water are effective controls of some insect pests if you catch the damage early. Many insect problems can be reduced or eliminated by removing a few affected leaves or plant parts.

Protect the beneficial insects in your landscape by avoiding blanket applications of pesticides. Treat for specific pests and only treat the affected plant. Avoid using broad-spectrum pesticides. Remember, broad-spectrum pesticides are not selective; they also kill beneficial insects.

Safer alternatives to traditional, chemical pesticides include insecticidal soaps, horticultural oils and products containing a bacterium called Bacillus thuringiensis.

Safer solutions for landscape pests

Insecticidal soap
Make your own effective spray with 2 1/2 tablespoons of liquid dishwasher soap in 1 gallon of water. Spray liberally on affected plants and repeat application if necessary.

Horticultural oils
Labeled as such in garden centers, these products are used as sprays. To make your own oil spray, mix 2 1/2 tablespoons of vegetable oil, 2 1/2 tablespoons of liquid dishwasher soap and 1 gallon of water.

Bacillus thuringiensis
A bacterium that infects and controls caterpillars. Available commercially in liquid (spray) form and dusting powder.

Beer
In areas where slugs are a problem, place shallow pans of beer on the ground.

Active ingredients in pesticides commonly used in home landscapes

The following compounds are moderately persistent in the environment, highly toxic to aquatic life and hazardous to terrestrial life. Be very cautious if you apply pesticides containing the following active ingredients:

Chlorpyrifos Chlorothalonil Diazinon

Endosulfan Ethoprop Trifluralin

The following compounds either degrade more rapidly under field conditions than those listed above, or they are moderately toxic to aquatic life and/or terrestrial wildlife. Use caution if you apply pesticides containing the following active ingredients:

Acifluorfen Atrazine Carbaryl

Disulfoton Malathion Vernolate

The following compounds have low aquatic toxicity and degrade fairly rapidly. As with any pesticide, however, caution should be used in their application:

• 2,4-D

[Sources: National Oceanic and Atmospheric Administration and the Environmental Fate and Effects Division of the U.S. Environmental Protection Agency Office of Prevention, Pesticides and Toxic Substances.]

Common Plant Pests and Least-Toxic Controls

Aphids
Winged or wingless; pear-shaped body; usually green; may be yellow, black or other color; typically congregate at twig tips; leaves may be twisted or distorted; ants or sooty mold may be present.

Natural controls: Lady beetle adults and larvae, lacewing larvae, syrphid fly larvae, parasitic wasps.

Other controls: Flush from branch tips with water from hose, apply insecticidal soaps.

Mealybugs
1/16- to 1/8-inch long; soft bodies; well- developed legs; bodies covered by powdery white coating that may also surround egg masses; attack leaves, twigs, roots; lots of ants; white, mealy wax deposits; sooty mold.

Natural controls
Lady beetles, lacewing larvae.

Other controls
Spray with horticultural oil. If oil spray fails, systemic pesticide may be applied to root system, affecting only pests that feed on plant sap.

Scales
About 1/16-inch in diameter; various size, shape and color; some produce honeydew (sugary secretion); body hidden under waxy scale covering; mature scales are stationary and feed on leaves, twigs, stems, fruit; yellow spots on top of leaves with scale underneath; ants; sooty mold

Natural controls: Lady beetles, parasitic wasps.

Other controls: See methods for mealybugs.

Whiteflies
Adults appear as white specks on plants; deposit eggs on underside of leaves; stationary larvae are oval, flat, transparent-to-greenish color when alive and dull white when dead; ants; sooty mold; adult flies around or on plant; larvae under leaves.

Natural controls: Fungi (white, orange or tan; most effective in humid weather), parasitic wasps, lady beetles.

Other controls: Spray with insecticidal soap. Follow with horticultural oils if necessary.

Caterpillars
Larvae of butterflies and moths, chew on foliage causing skeletonized leaves and notches, greenish fecal pellets on foliage, caterpillars observed.

Natural controls: Birds, predatory stinkbugs, big-eyed bugs, lizards.

Other controls: Spray or dust with Bacillus thurigiensis. Most effective when caterpillars are small.

Thrips
Tiny (1/32-inch); wings; scar leaves and drink sap from wounds; plant may be dull, grayish; curling, distorted leaves.

Natural controls: None identified.

Other controls: Apply horticultural oils

Spider mites
Tiny (1/32-inch); oval bodies; red, yellow or greenish; may have spots; adults spin loose webs on foliage; reproduce rapidly in hot weather; injuries to plants look like light color dots, giving leaves dull, gray green, stippled appearance. Fine, loose spider webs; ashy looking residues.

Natural controls: Lady beetles, predatory mites.

Other controls: Flush with water, then alternate with soap and oils if necessary.

Mole crickets
Up to 1/2-inch long, velvety brown, front legs flattened and adapted for burrowing; affects Bahia and Bermuda grass, turf may be spongy and thinning, 3/4-inch round holes with signs of tunneling, infestation likely to occur in same area each year. Test for infestation by flushing area with soapy water, crickets will surface if present.

Natural controls: Red-eyed fly, beneficial nematode, ibis.

Other controls: For chronic infestation consider replacing turf with trees, shrubs or ground covers. May spot-treat infestations in June with materials labeled for mole cricket control. Use bait later if necessary.

Chinch bugs
Adults 1/5-inch long, black and white patches on wings, young nymphs smaller and reddish, attacks St. Augustine grass, yellowing turf grass, often in stressed areas in full sun or near paved areas.

Natural controls: Big-eyed bug, earwigs.

Other controls: Avoid high fertilizer rates. Maintain St. Augustine at height of 3 inches in sun and 4 inches in shade. Use chinch bug-resistant grass varieties (Floratam, Floralawn, FX-10). Spot-treat infestations with materials labeled for chinch bugs.

Fleas
Small, dark colored, 1/8-inch long, can hop some distance, obvious effects on pets and people, prevalent in areas where pets bed down or dig holes.

Natural controls: None identified.

Other controls: Spot-treat pet bed/outdoor resting areas with soap solution. Other least-toxic products are boric acid and those containing fenoxycarb (an insect growth regulator) that may be effective in shade. Beneficial nematode products are the newest outdoor control.

Ants
Three body segments; sizes range from 1/16-1/2 inch, depending on species; most species not harmful; mounds, ants in trails and on plants; controls not recommended in landscape unless fire ants are a problem.

Natural predators: None identified.

Other controls: Safest chemicals for fire ants include those with avermectin. Be sure material is dry/fresh and apply in morning or evening around edges of mound. Do not disturb mound.

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