- The colonies occur on bark and aphids do not infest the foliage or fruits directly.
- Galls often form on the branches at the point where aphids have fed.
- The galls often split open allowing entry for diseases such as canker or Gloeosporium sp.
- The main damage is caused by contamination of fruits and foliage with honeydew, wax, dead aphids etc..
- Although woolly aphid colonies are conspicuous, the amount of injury to the established tree is probably less than the appearance suggests.
- At harvest, infestations can be a severe nuisance to pickers.
Other pests with which woolly aphid may be confused
Woolly aphid infestations and the damage they cause are unique on apple and are unlikely to be confused with other pests.