We have a confined (by wood deck) silver maple in our backyard. 42″ across. More than 2 stories high. Arborist took a look at it just this past fall and said there was nothing wrong with it. Usually gets trimmed every 3 or 4 years. Very close to back of house (10′?). Seen these green leaves fall with what looks like a weird kind of growth on them. (I shot it on my skin, so ignore that!). What is it? Please & thank you.
Thank you for contacting Toronto Master Gardeners. You are to be commended for taking such great care of your majestic Silver Maple (Acer saccharinum). Silver maples are known for having weak wood/brittle branches so proper pruning is essential to prevent damage from high winds or ice/snow in winter.
We received a similar query from another gardener earlier this week. Based on the photo of the leaf you submitted, the bumps on your silver maple tree’s leaves are called galls. A common insect, Maple bladdergall mite (Vasates quadripedes Shimer), is most likely the cause of these galls. Refer to Infestation in old maple tree for more details.
Heavy infestations can impact photosynthesis for the impacted leaves, but generally the galls will not impact the overall health of your tree.
June 28, 2024