Black Cherry Aphid

The black cherry aphid (BCA) is the most common aphid attacking cherry in most parts of North America. It is a European species that can cause serious injury to sweet cherries and may occasionally cause injury to tart cherries.

The adults and nymphs are readily identified by their shiny black coloration (photo above), since no other aphid of this color attacks cherry. The adults are soft-bodied insects that measure about 1/8 inch (3.2 mm) in length and exist in both winged and wingless forms. The nymphs are smaller in size, but are otherwise identical in appearance to the wingless adults. The shining black, oval eggs are extremely small, less than 4/100 inch (1mm) in length.

Although it can survive on wild cherries, the BCA prefers commercial cherry varieties. While it will infest and feed on tart cherry, it greatly prefers sweet cherry varieties. `Napolean’, `Black Tartaria’, `Schmidt’, and `Windsor’ are the most susceptible varieties to injury from this insect, while `Dikeman’ and `Yellow Spanish’ are not seriously injured. Tart cherry varieties such as`Montmorency’, `Early Richmond’ and `English Morello’ are attacked less frequently, and when attacked the injury is slight. Alternate summer hosts include water cress, peppergrass and other members of the mustard family.

Life cycle:Adults and nymphs are readily identified by their shiny black coloration. The adults are 1∕8 inch long and have both winged and wingless forms. Nymphs are similar in appearance, but smaller.Although the aphid can survive on most cherries, it prefers commercial cherry varieties, greatly preferring sweet cherries. Napolean, Black Tartarian, Schmidt, and Windsor are most susceptible to injury, while Dykeman and Yellow Spanish are not very susceptible.Alternate summer hosts include water cress, peppergrass, and members of the mustard family.The black cherry aphid overwinters as an egg on the bark of small branches. The eggs begin to hatch as soon as cherry buds break, with young aphids moving to new green tissue. After 3 to 4 weeks wingless, stem mother females have established large colonies on growing shoots.

Two to three generations occur on cherry trees by early July when most of the aphids move to alternate hosts for the summer. In September or October winged males and females return to cherry trees, mate, and lay eggs.Feeding causes curling and stunting of leaves and stems. Heavy infestations may kill young trees and reduce crop quality and quantity and return bloom on mature trees. Honeydew from these aphids also causes the growth of black sooty fungus.

Damage:Low to moderate numbers of leaf-feeding aphids are usually not damaging in gardens or on trees. However, large populations cause curling, yellowing, and distortion of leaves and stunting of shoots; they can also produce large quantities of a sticky exudate known as honeydew, which often turns black with the growth of a sooty mold fungus. Some aphid species inject a toxin into plants, which further distorts growth. A few species cause gall formations.Aphids may transmit viruses from plant to plant on certain vegetable and ornamental plants. Squashes, cucumbers, pumpkins, melons, beans, potatoes, lettuces, beets, chards, and bok choy are crops that often have aphid-transmitted viruses associated with them. The viruses cause mottling, yellowing, or curling of leaves and stunting of plant growth.

The losses can be great, they are difficult to prevent through the control of aphids because infection occurs even when aphid numbers are very low: it only takes a few minutes for the aphid to transmit the virus while it takes a much longer time to kill the aphid with an insecticide.A few aphid species attack parts of plants other than leaves and shoots. The lettuce root aphid is a soil dweller that attacks lettuce roots during most of its cycle, causing lettuce plants to wilt and occasionally die if populations are high. The lettuce root aphid overwinters as eggs on poplar trees, where it produces leaf galls in spring and summer. The woolly apple aphid infests woody parts of apple roots and limbs, often near pruning wounds, and can cause overall tree decline if roots are infested for several years.

Control:Hosing plants can lethally injure aphids and very few surviving aphids that are knocked to the ground can successfully find their way back onto their host plant.Some flowers that are perennial, but dieback to the ground in fall, have problems with aphids in the spring. Columbine, lupines and perennial asters are examples. With these plants the eggs of the aphids are laid on the stems in fall, near the point where new shoots will emerge the following spring. Spring problems with these aphids can be prevented by removing the old top growth that contains the eggs before plants emerge in spring.

Some pesticides, such as certain carbamates and pyrethroids, encourage outbreaks by killing parasites. These should be used sparingly when woolly apple aphids are present. An application of a summer aphid treatment or diazinon will control woolly apple aphids. There are presently no control methods for underground aphids.The best control of woolly apple aphid is genetic. Plant resistant rootstocks like M.106. The Malling Merton series of rootstocks was bred specifically for woolly apple aphid resistance.

If you have any questions about how to get rid of ants check out the rest of our website or go to our blog at http://nypestpro.blogspot.com.

Beyond Pest Control.

Our pest control specialists service all NYC boroughs, including Queens, Brooklyn, Bronx, Manhattan, Long Island (both Nassau & Suffolk counties), Staten Island and even both Westchester & Rockland counties.