Aphids on many trees and plants

Submitted Photos

Aphid numbers have built up very quickly the past week to 10 days and are infesting a wide variety of trees, shrubs and garden flowers, fruits and vegetable.

Aphids are a small, soft bodied insect. They have both winged and wingless form. They are somewhat unique as the females do not require a male aphid to reproduce. They produce live young rather than lay eggs, which makes for faster infestation numbers. They come in a wide variety of colors from green to black to pink.

“Honey Dew” is the sweet excretion of aphids that people mistakenly think is trees sap. The aphids feed by sucking the plant juices which are high in plant sugars which makes “Honey Dew” so sticky. In large trees, there is nothing that should or can be done. The trees are not negatively affected due to their size. Small, newly planted trees and shrubs can be treated as they are a bit more vulnerable to damage.

Aphids prefer to feed on the underside of the plant’s leaves. One of the first signs of aphid infestation are crinkled or rolled leaves. Inspecting inside the rolled leaf will expose the aphids.

There are a number of control options. The simplest is a strong spray of water from a water hose. This will was them off and most will not be able to repopulate the plant. For those preferring other organic mean, Neem Oil, Diatomaceous Earth, insecticidal soap spray and other horticultural oils. As with any pesticide, read and follow the label directions.

Insecticides which control aphids include Sevin, Malathion and Tempo. These insecticide are not labeled for all plants and food crops. So be sure to read the label for those fruits, vegetables, shrubs and trees that the insecticide can safely be used.

Spider Mites

Spider mites are a tiny mite which suck plant juices and may inject a somewhat toxic compound into the plant leaf. The first signs of mite infestation are bleaching of leaves and speckling discoloration of the leaves which are usually seen between the veins of the leaf veins. There may or may not be tiny webbing on the back of the leaf. If spider mites are present they will show as tiny black specks on the underside of leaves.

Spider mites are extremely small looking like a speck of dust. The best way to check for them is either with a magnifying glass or by holding a white sheet of paper under the leaf or branch and tapping on the top of the leaf or branch. Then look on the paper for the black specks that will move across the paper. These would be the mites.

The first means of control of small trees and shrubs as well as garden plants is a hard spray of water under the leaves. They are found on the underside of the leaf, and washing them off with water can be quite effective control. They are very poor climbers and will likely not be able to re-infest the plant.

Horticulture soap, Neem oil and other horticultural oils are effective controls applied to the underside of leaves. Mitcides that contain the chemical bifenthrin are effective but are not registered for safe use in all plants. Read the label to be sure it can be used on the plants you want to treat. This is especially critical of edible fruits and vegetables.

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