Woolly aphid

Q: How do I identify and control Woolly Aphid?

What it looks like:

If there’s such a thing as a glamorous aphid then this one is quite the Queen of the catwalk in its fur coat. It’s also gregarious, liking to surround itself with like-minded individuals. And trouble flares when you start to have a few of them in one place. You’ll spot them between April and October. Webby, waxy swellings on the stems of pyracantha, cotoneaster, edible apple and crab apple trees, give the game away.

What it does:

Under the fur coat carapace, they chew and gnaw at your shoots. They drink the sweet sap and can pass on a virus. The ugly swellings it leaves behind can also be a start of canker. In addition, any stragglers overwinter in cracks and crevices on trees ready to start a fresh attack the following year. If you don’t sort them out, they will destroy.

How to sort:

  • The first line of attack is going to require some elbow grease (not currently available online)  in spring and early summer. If there are just a few colonies, then scrubbing the waxy, webby swellings off with a stiff-bristled brush should stop the takeover bid.
  • Being such a tasty treat woolly aphid has several natural enemies such as ladybirds, lacewings, hoverfly larvae and sometimes - under the right conditions - a parasitic wasp called Aphelinus mali. They will all help control numbers but never get rid of  all the infestation.
  • It’s also reported that earwigs on fruit trees can reduce numbers and on fruit trees they do not cause damage (growers of dahlias know a different side to earwigs). Providing shelters such as flower pots loosely stuffed with hay in trees, or upturned on canes, can help increase numbers.
  • If nonchemical tactics fail, the chemical treatments come into play. Obviously, use them with caution especially if fruit is to be eaten. On edible apples, including crab apples used for jam making, the trees can be sprayed thoroughly, there are several products now that are safe to use on edibles. Manufacturer’s instructions should always be followed, including the minimum period that needs to be left between treatment and picking the fruit on apple trees. One more note of caution in the interest of protecting our pollinating insects, plants in flower should not be sprayed.

So, keep a vigilant eye on your trees and shrubs as named, look out for the glamorously attired woolly aphid meeting places and take action as soon as you spot it.

Garden Pests