Bumpy Maple Leaves? Gall Mites Might Be The Problem

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Have you seen these bumps on your Maple trees? (Hope not!)

Red, unattractive bumps, or ‘galls’ luckily do not cause damage to your trees, but sure look like they do! These red protrusions are caused by an insect such as the Bladder Gall Mite, or a Spindle Gall Mite which are found to be lurking around your trees early in the spring season. The red bumps are a result of the mites chewing on the tree leaves specifically in the growing season. These mites are aiming to stimulate new tissue growth in which they lay, and hatch their eggs. When the leaf is affected the symptomatic result is a chemically induced mass growth of abnormal cells.

Funny enough, these little pests only affect three types of Maple Trees, Red Maple, Sugar Maple, and Whitebark Maple.

Though the health of the host tree is rarely affected, the visual (cosmetic) health of the tree is commonly associated as poor with an infestation. For this reason, UTS gets requests often to reduce the look of Gall Mites ‘nesting’.

Here are a few things that UTS Tree Care can do to assist in the reduction of Gall Mites:

  • Use Environmentally Friendly Lyme Spray early in the season prior to infestation, and again a year later.
  • Careful, selected pruning early in the year to remove affected areas
  • Integrated Pest Management planning for future preventative measures.
  • Finally, isolating severed, affected material from other trees, and surrounding plant life is required. From cleaning the ISA Certified tech’s clothes, to tying up the leaves, bark and equipment for proper disposal and sanitization.

It’s our philosophy at UTS Tree Care to work on the health of the tree, and not to simply correct the symptoms. It’s been proven that Gall Mites, like most infestations, are more likely not to affect trees that are strong, and healthy. Tree assessment, fertilization, pruning, and a long term tree health care program is what will significantly reduce the chances of these red bumps popping up on your property.

Not sure what you’re looking at on your tree? Give UTS Tree Care a call, and we’ll come out to your property and give you a free assessment.

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