Aphids are small (1/8"), soft-bodied insects that feed by sucking plant sap. They are often found in clusters. Look at growing tips, flower buds, and backs of leaves frequently during the growing season. 

LESS TOXIC CONTROLS 

• Wipe off small colonies with gloved hands. 
• Pinch or prune off severely infested portions of the plant. 
• Spray with insecticidal soap (available in nurseries). Always test a small portion of foliage before treating the entire plant. Some plants are very sensitive to soap sprays. 
• Spray with highly refined "superior" or "summer" horticultural oils which are fairly gentle on natural enemies (mix 4 teaspoons of oil in 1 quart of water). 

• Do not over fertilize because aphids reproduce more quickly on plants with high levels of nitrogen in their leaves and buds. Use slow-release fertilizers such as compost, sewage sludge, urea-based fertilizers, or encapsulated materials. 
• Exclude ants from aphid-infested plants because ants protect aphids from their natural enemies. Encircle woody shrubs or trees with sticky pastes or with Teflon(tm) tape (both are available in nurseries). 

Cabbage family plants and some lettuce can be suspectable to Cabbage Loopers. Look for single dome-shaped eggs or green caterpillars. Caterpillars eat irregular holes in leaves and are most active in warm weather.

• Inspect plants twice a week and crush eggs and worms.
• If hand picking isn't working, spray with the caterpillar disease, Bacillus thuringiensis (B.t.). It affects only caterpillars, and they must eat the material in order to die. B.t. is available in nurseries under various trade names. 

• Floating row cover can be placed over entire crop at seeding or transplanting. Cut the fabric larger than the planted area and leave some slack for plant growth. Secure with soil and rocks. Periodically, check under the row cover for other insect problems.

Cabbage family plants are suspectable to Cabbageworms. Look for tiny, pale yellow eggs on backs of leaves after transplanting. Light green caterpillars will appear in little over a week and lie flat on leaves chewing irregular holes. 

LESS TOXIC CONTROLS 

• Inspect plants twice a week and crush eggs and worms. 
• If hand picking isn't working, spray with the caterpillar disease, Bacillus thuringiensis (B.t.). It affects only caterpillars, and they must eat the material in order to die. B.t. is available in nurseries under various trade names. 

• Floating row cover can be placed over entire crop at seeding or transplanting. Cut the fabric larger than the planted area and leave some slack for plant growth. Secure with soil and rocks. Periodically, check under the row cover for other insect problems. 

Cutworms can attack many tender, young plants. Cutworms are fat brown worms found in burrows in the top few inches of soil or under the litter on top of the soil. Suspect cutworms if you find seedlings chewed off at or just above the soil line. They feed at night and will also feed on leaves and buds. 

LESS TOXIC CONTROLS 

• Hand pick during the day searching in widening rings around the stems of seedlings. 
• Start vegetable and flower seedlings indoors and plant outside when they are large enough to withstand some damage.
• Surround seedlings with 4 inch high collars of cardboard (juice cans or toilet paper tubes) pushed into the soil about an inch. 
• Cover individual seedlings with cones made of window screen. Push cones down into the soil an inch or two. 
• You may be able to reduce cutworm damage by clearing weeds (especially grass and grass-like weeds) in the garden before planting.
• Eliminating all weed food for cutworms for at least 10 days before seedlings come up will starve the cutworms. 

Earwigs attack leaves of seedlings or older plants. Look for shiny brown insects, with pincers on their rear ends, in plant crevices, near the soil surface, under flower pots, or boards. Earwigs are often blamed for damage done by other insects or snails and slugs because they like to curl up in plant crevices and holes in fruit during the day. To be sure of who is causing the damage, check with a flashlight on several consecutive nights.

LESS TOXIC CONTROLS 

• Hand pick earwigs and crush on a hard surface. 
• Set out short lengths of bamboo or rolled-up newspaper to trap earwigs. Check in the morning for earwigs and crush. 

• Spread a thick organic mulch on the soil (earwigs will eat the mulch). Add another layer of mulch when the original layer decomposes. 
• Start seedlings indoors and plant outside when large enough to withstand damage.

Lawn weeds are easily detectable. Most people can tolerate a few weeds, so make it your goal to keep weed numbers low enough to prevent significant visual damage. The number you can tolerate is a personal decision. 

LESS TOXIC CONTROLS 

• Dig out small patches of weeds with a sharp weed-knife or v-shaped dandelion knife. Immediately loosen the soil and sow grass seed in the bare spot. 
• Spray weeds with herbicidal soap (avail- able in nurseries). This soap will also damage grass, so cover surrounding grass with cardboard or plastic. 
• Do not use lawn fertilizer containing herbicides. 
• Plant appropriate grass species for your area. 
• Fertilize your lawn in spring and fall with a slow-release fertilizer (see aphids). 
• Lawns mown too close to the ground are very susceptible to weed invasions. Set the mowing height at 2-1/2" to 3" so the grass can shade out weeds. 
• Aim for slow, deep irrigation. Over- or under-watered lawns are also susceptible to weed invasions. 
• Aerate your lawn regularly. 
• Consider planting drought-tolerant ground covers instead of grass. 

Seedlings can sometimes be severely damaged by leafminers, but in general they are a cosmetic problem and in many cases will not cause significant damage to the plant. Leafminers like spinach, beets, chard, and some ornamentals. Look for grey, light green, or brown trails (or blotches) in leaves. Leafminers feed between the upper and lower surfaces of the leaf. 

• Hand pick and destroy affected leaves. 
• If problems are severe, try spraying young plants with horticultural oil (see Aphids). Or cover the soil around the affected plants with plastic mulch (available at nurseries) to prevent the larvae that fall off the plant from getting into the soil to pupate (spin the cocoons). 
• Pesticides will not work. 
• Plant seeds or seedlings under floating row covers (see Cabbage Loopers). 
• With some plants, especially columbine, adequate watering can reduce infestations. 

Mites feed on many vegetable, ornamental, and indoor plants. Mites are tiny, 8-legged creatures. Inspect the undersides of leaves with magnification of 15X or greater. Look for stippling, silvering, or yellowing of upper surface of leaves and fine webbing under and between leaves. 

• Avoid using broad-spectrum pesticides because they will kill more of the beneficials than the pest mites. 
• Isolate infested indoor plants so they will not infect others. *Spray with insecticidal soap or horticul- tural oil (see Aphids). *Dust with sulfur, but do not use horticul- tural oils for a month after sulfur application because sulfur residues can cause oil sprays to burn plant leaves. 
• Keep plants well watered because water- stressed plants are more susceptible to mites. 

Powdery mildew attacks many plants. Early symptoms are raised, blister-like areas that cause leaves to curl. Later leaves are covered by a greyish-white, powdery fungal growth. Unopened flower buds can become white and fail to open. This fungus prefers young succulent growth. 

LESS TOXIC CONTROLS 

• Prune out damaged foliage or flowers. 
• Wash new growth with a spray of ordinary water. Powdery Mildew thrives in cool conditions. 
• Spray new growth with antitranspirants (available in nurseries). These are waxes, silicones, or other compounds that make an invisible barrier to prevent powdery mildew spores from penetrating plant tissue. 
• Use horticultural oil and baking soda (see horticultural oil label for instructions for application rate). Spray at the first sign of the disease and repeat whenever new symptoms appear. 

• Plant disease-resistant varieties (this applies mainly to roses). 
• Avoid over-fertilization and use slow- release fertilizers (see Aphids). 

Many garden roses, especially hybrid tea, floribunda, and grandiflora are susceptible to rose diseases such as black spot and rust. Symptoms of black spot are circular black spots with fringed edges on canes and on underside of leaves surfaces. Symptoms of rust are small orange or yellow pustules on any green portion of the plant. 

• In mid-January, remove all leaves from the plant and destroy them, prune and destroy any infected canes, and then apply a layer of mulch around the plant (the mulch acts as a barrier between the plant and the overwintering disease spores on the debris beneath the plants). 
• In fall, rake up all leaves and petals and apply a layer of mulch. 
• Spray with a fungicidal soap (available in nurseries). 
• Spray with a baking soda mixture (see Powdery Mildew). 
• Spray with a sulfur-based fungicide. Be sure to cover the tops and undersides of the leaves paying special attention to the growing tips. Begin application early in the season. Do not apply sulfur when temperatures exceed 85 degrees Fahrenheit. 
• Plant disease-resistant varieties, such as Rosa Banksiae or polyamtha and rugosa roses. 
• Plant roses where they will get six or more hours of sun and good circulation. 
• Keep plants well watered. 
• Prune roses so they have open centers. 
• Keep foliage dry by avoiding overhead sprinkling, or sprinkle at time when foliage will have time to dry before nightfall. 
• Avoid over-fertilization and use slow- release fertilizers (see Aphids). 

Snails and slugs will eat almost any kind of plant. Look for them at the bases of leaves of plants, in moist cool areas, or under debris, boards, and flowerpots. Snails and slugs leave a shiny slime trail on leaves or soil. 

• Hand pick and crush or drop into soapy water. Hunt at night between 10 p.m. and 11 p.m. with a flashlight or, in daylight, look in smooth, dry, dark hiding places. 
• Remove pearl-like egg clusters to reduce populations. 
• If you use commercial baits, place them in a covered container such as a plastic margarine tub, and cut a hole for the snail/slug's entrance. 
• Set out traps such as overturned flower pots or plastic garbage bags laid on the soil or on groundcovers. Check in morning. 
• Ground beetles, found in compost, will eat slugs and snails. 
• Remove garden debris (loose boards, old pots, etc.) unless you're using them as traps. 
• Remove or reduce the area of favored breeding sites such as ivy, nasturtiums, and clumps of iris. 
• Install a band of copper sheeting (avail- able at nurseries) around tree trunks, flower pots, or planters. 
• Dry sawdust paths will deter snails and slugs. 

Sow and pillbugs like plants in a moist environment or on the verge of decay (e.g. ripe strawberries, ripening tomatoes that are touching the ground, etc.). Year-round, look in debris and on the soil surface for grey, segmented bugs that curl up into a ball when disturbed. 

• Hand pick and crush. 
• Make baits with cubes of raw potato (check daily and trowel the bugs into a plastic bag or a pail of soapy water). 
• Spread mulch on soil (see earwigs). 
• Grow plants up trellises or at least keep ripening fruit off the ground. 
• Remove dying lower leaves to improve air circulation. 

Beans, poinsettias, and tomatoes are suspectable to whiteflies. Look at leaf underside for small, light-colored speckled larvae, or tap the plant to see if small white insects flutter about (during warmer months). 

• Avoid the use of broad-spectrum pesti- cides; they can cause a whitefly outbreak. 
• Spray bad infestations with insecticidal soap or horticultural oil (see Aphids). 
• Vacuum the plants when the air is cool. 
• Install yellow sticky traps (yellow attracts these insects). 
• Do not over-fertilize with nitrogen. 
• Prune and remove badly infested leaves and plants. 

Artwork: Copyright Jenny Speckles 1997