Dogwood tree showing symptoms – but what’s the cause?

Credit: Flickr / lcm1863

Q: I live in Ladysmith B.C. In spring/early summer, my dogwood tree, which is situated in an open area, facing east, begins to drop its leaves.

Upon further inspection, I noticed the underside of the leaves had small white bumps on them, and the tips of the leaves had turned black. The garden centre said it was mealy bugs, but everything I’ve read suggests this is an indoor/tropical plant problem, not one associated with dogwoods.

Any suggestions?

Yes, I would agree this could not be a mealy bug problem, but it could be “scale”. While I don’t have sufficient information to determine the type of dogwood you have, I would suggest making sure the insect is properly identified before actually treating it. You might want to bring a sample to your local garden centre or nursery for verification.

Assuming it is scale, the treatment is to physically scrape it off, using a garden hose to rinse it. Be careful not to be too rough on the plant. During the winter months, use a dormant spray (oil) and apply as directed. Make sure the spray is applied thoroughly since it works mainly by contact. Two applications may be necessary.