Boring insects are very difficult to control. Typically, you would need to utilize some sort of systemic insecticide that will be assimilated by the tree's roots and carried up into the growing tissue. And if the damage is already significant, that might not be much help. You might need to hire a consulting arborist (ISA certified) to assess the long term viability of the tree and methods of treatment.

"The tree did not fully bloom this spring." I assume you mean last spring as this spring hasn't yet arrived......not for another 3 weeks or so and even that may be a tad early for a red maple to be in flower, even in a mild climate!

Thanks for your reply. I must say--a lot of my post came from another forum but it can be related to my situation. MY tree did leaf out, last spring, very well, I guess. What do you mean by-flower? Not knowing much about trees, don't quite know what to expect to see. This was my reply on that other site---It is boring up into a hole from which a large limb was removed by prior owners. This hole(tunnel) goes up at least 3-4 ft. at last look, sev mos ago. Appreciate any comments, info, spray I can use in hole. I first realized this problem about 1 1/2 yrs ago. Tree is large--appox. 35-40 ft tall.

Bloom = flower. Although they do not necessarily look like common garden flowers, all non-coniferous plants bloom or flower, including red maples, which can have a rather showy flower as maples go.

And please reread my previous post. Spraying something into the hole is not a viable solution for a boring insect. You need a systemic at the very least but you would be best served by hiring a tree professional as the damage already sounds extensive.

Thank you for the flower link and your advice. We had 6-7" of snow last night. Will be melted by Monday. Supposed to in 70s next week, Im done with snow!!

Thanks again.

fredda

Hey. I'm right there with you. Woodpeckers have been having a field day on my maples for years. An October Glory last year's spring put out so many whirly gigs that I thought the whole top of the tree was dead at first. Then I realized the struggle.

I had a bonsai expert come out for the day last spring to look at my 100+ collection of Japanese maples and tell me what I was doing wrong, right, and could do better. He looked at my larger trees and showed me where borers had gotten in. Right down to Beech borers.

At his very strong recommendation, I gave up and gave in and started with the big guns. Bayer Advanced 701910 12 Months Tree and Shrub Protect and Feed Granules, 10-Pound. Granules for potted trees, and and a less expensive version (same ingredients) of the liquid form. Compare-N-Save Systemic Tree and Shrub Insect Drench for the larger trees.

Because I have so many acres of beautiful trees, I started buying this weekly over the winter. But that's irrelevant to the question. It really became a question of losing 50+ beautiful, shade giving trees, or chemicals. I chose to save the trees I'd planted over the last 10 years. I did, also, spray into the holes. I couldn't resist, although I realize it was probably wasting product. The thing is, the cambria (?) layer of your tree might be compromised, bringing it to a slow death. Better to give this stuff a try than to lose a tree.

My struggling-est Pacific Sunset, whose trunk looks almost braided, has tried so hard to kick the bugs over the years. Last summer it had much thicker flush of leaves than previous years. Everywhere I'd pruned looked diseased and peeling. Borers. I couldn't figure it out for years.

Anyway, this is my 2nd year and I'm actually going to start treating the bigger trees during these two beautiful days. You can do it any time during the year.

I'm over between Bowie and Upper Marlboro, towards Annapolis. I know your area.

Good luck.

CEFreeman---

Read your reply with interest. Being an older person, fixed income, just not quite ready to start this journey. Thinking of spraying Dursban up into the tunnel that ? has gnawed upwards appox 4 ft. Its the "shavings" at the bottom of the hole that have me puzzled. What would make that? The spray may make no diff, but then I will know that. Any more thoughts are welcome.

thanks, fredda

Don't waste your money. My opinion.
If you're going to treat with something, get some of that Bayer or Compare-n-save. You need something systemic.

The shavings are probably where whatever it is is chewing its way through the center of the tree. How do you know it's 4'? Are you sticking something up in there? As you've shown, it's only going to get worse.

Try this: Stuff something in it to block the hole. A sock, tennis ball, something. I'm just curious if whatever it is will push that out of the way? It might be some strange animal we've never heard of.

"Thinking of spraying Dursban.........."

You do realize that Dursban ( or more correctly, the chemical that comprises the active ingredient in Dursban) has been banned from any household usage since 2001? And that this is a serious neurotoxin that can cause neurological effects, persistent developmental disorders and autoimmune disorders. Children, pregnant women and seniors tend to be more affected by these types of chemicals due to increased sensitivity and less efficient autoimmune systems.

And Dursban/chlorpyrifos was never registered for control of boring insects anyway. As noted above - save your money and maybe save your life and use a properly registered product and only as the label indicates. And get rid of the other poison promptly and through proper hazardous waste channels. It is now illegal to own!!