pest control gnats

Identifying Common Plant Pests

The most familiar green plant pests are aphids, cyclamen and spider mites, mealy bugs, scales, white-flies and thrips. If one of these pests infests a plant, isolate it immediately to prevent spreading to other plants.

Aphids are small, soft bodied insects with varied color. They are found on new growth or on the lower leaf surfaces sucking plant juices and excreting a sap called honeydew which attracts ants and supports sooty mold growth. Aphid infestations may occur on almost all plants and often cause leaf curling or distortion. To eliminate these pests, wash leaves with soapy water or dab with a cotton swab containing alcohol or use an insecticide.

Mealy bugs are oval-shaped, small, soft bodied insects which cover plants with a cottony or powdery material along the veins of the leaves or where the leafstalk joins the stem. They will stunt plant growth and cause leaf wilting and loss. Mealy bugs also excrete honeydew. Control these pests by dabbing with alcohol or washing with soapy water. Insecticide can also be applied.

Cyclamen mites and other microscopic mites sometimes infest green plants but are too small to see. They attach themselves to young growth or buds and suck plant juices. These mites cause leaves to become curled and buds to become deformed. To eliminate cyclamen mites, wash leaves with soapy water and apply an insecticide.

Red spider mites are small, red or brown colored plant pests, which feed by sucking plant juices on the undersides of leaves. They spin small webs on plant stems and leaves and cause bronzy, yellowish leaves and often speckling. Control these pests by washing with soapy water, dabbing with alcohol and applying an insecticide.

Scales are small, brown or grayish colored insects with shell coverings which suck plant juices and excrete honeydew. They cause stunted plant growth and leaf discoloration. Scales may be found on a variety of green plants. To control scales, scrape the pests off the plant, wash with soapy water and spray with an insecticide.

Thrips are small, dark-colored pests which feed on plant leaves and flowers. They injure plants by shredding plant surface tissues to obtain juices. Severe infestations result in distorted flowers and leaves which turn yellow and fall. To control thrips, wash with a forceful stream of water and spray with an insecticide.

White-flies may be found in two forms. Adult white-flies are small, white winged insects, and immature white-flies are small insects which attach to undersides of leaves to suck plant juices. They excrete honeydew as they feed which attracts ants and supports sooty mold growth. White-flies flutter about when a plant is disturbed. They will cause leaves to yellow and drop off. To control white-flies, dip plants in a soapy solution or spray with an insecticide.

Other occasional uninvited plant pests include: ants, which damage roots; fungus gnats, which feed on young roots and the succulent parts of the plant close to the soil; caterpillars, which feed on plant leaves and stems, and occasionally snails and slugs, which feed on roots, leaves and stems. These pests can generally be exterminated with pesticides.