Question
QUESTION: HiJim:

We chatted prior to Thanksgiving. My problem you  determined was wood borers and a fungi, you recommended Merit to treat the insect problem.

I found a bottle of liquid Merit by Bayer($32.00 for 32oz.). Going by the directions on the bottles I would need a couple gallons($$$$) to apply to the root bed. Since the tree is over 100" in circumference. I called Bayer whose  representative stated the product shouldn't be sprayed or poured onto the affective area.

Jim I am confused what should I buy and how do I apply the Merit. Is it to late in the year to treat the the borers? I really would like to fill in the hole with foam.
I covered the hole only to have a squirel chew a hole thru the plastic, I saw him poke his head out the hole.

Thanks,

Charlie

ANSWER: I guess I under estimated the size of the hole. The Merit can be sprayed on the trunk around the hole. This will keep the borers out. If a squirrel is living in the hole there is no need to spray the hole--the squirrel will keep the borers out. If the hole is large enough for the squirrel to make a nest (home) then the tree is hollow and the hole will go deep into the tree trunk. I doubt it can be filled. If you try to seal the hole with the squirrel in it the animal will dig its way out and keep the hole open. I would first make sure the squirrel is out of the hole then try putting some kind of plug or brace into the hole that can be used as a base to apply the foam onto. If you just spray the foam into the hole I ma not sure you can get enough into the large hole to fill the entrance. Then you can spray the foam in the hole entrance and close the hole. Make sure the out side of the foam does not exceed beyond the trunk surface.

Or just let the squirrel keep his home--if the squirrel is nesting there then there is not any water getting into the hollow or the water would run the animal out.

The fact that the tree is hollow will not effect the health of the tree except for possible breakage of limbs if the decay reaches into the limbs. Decay fungi are slow and the I would think the tree has many many years left before there would be a concern from limbs breaking off.

Sorry with out seeing the tree that is about the best I can do. I would recommend that you contact the Connecticut State Forestry agency and ask one of their Foresters to come take a look. This is free service. Here is a link to their contact web page.  fhttp://www.ct.gov/dep/cwp/view.asp?a=2697&q=329934&depNav_GID=1631#Service

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QUESTION: Jim

Thank You, for the forestry link!

By all means I will evict the squirrel before foaming. I am going to give it a reprieve, our weather forecast is 8+ inches of snow tomorrow and 12+ inches on Sunday.
Will the squirrel dine on the white borer worms?
You mentioned that water would force the squirrel out. I did clean out the combination of water and saw dust before covering the hole with double layered 4ml. plastic.
I hope it remains dry, it is a messy job scooping out the awful mess.
Should I disregard the manufacturers recommendations not to spray directly. You stated to spray at the opening, wouldn't it be better to spray directly on the area of the  borers?
Do you recommend chicken wire as an anchor, the foam I will be using is a high volume foam.
The product I found that contained Merit wasn't a spray but a liquid that was to be mixed with water. Is it all right to use said product?

Thanks Again,

Answer
What the squirrel will do is clean out the hole  to sound wood and then build its nest. This cleaning will keep the borers from entering the hole.
The chicken wire will be great --that will give the support for the foam to stick to.
Yes spray the Merit on the area that has borer damage. The liquid merit is mixed with water this makes the "spray" mixture.

I still would recommend that you call the Conn. Forestry agency and get one of their Foresters to take a look.