Borers in Larch - Insecticide advice?

I have what I believe to be a borer in an American Larch. It has a crack in the trunk that's been oozing sap for a couple of months. Unfortunately, when I first noticed it two months ago it was small and I didn't pay much attention, then I went away for a couple of months, and now I notice that it's much bigger and there's more sap flowing out.

From what I can tell, Nick Lenz's book is the only one that deals with it, but his advice is limited to a couple of paragraphs, and he doesn't mention any over the counter insecticides to use. From my other research, it seems like the good stuff is only available to professional arborists. So, I can't seem to find out if there's ant readily available treatment for this problem.

Has anyone else dealt with borers before? Is there a good brand name spray for them? Or is this a death sentence for my larch?

Thanks.

I have had borers before in my American Larch. It does not have to be a death sentence. Go with Nick's fumigation method, I think he uses two types of insecticides including a household pest killer and bags the tree inside a plastic bag over night for 2 nights. Make sure to take the bag off during the day when the sun is out.

When I had sap and saw dust coming out of a hole in my tree it was in a deadwood spot and I carved the hole deeper and deeper until I found the nasty things. Once I got them out I treated and I haven't had any issues since. Of course borers can really go nuts inside of a tree so this will not always work, they may be too far in.

After a collecting trip to Wyoming in the late 90s, I discovered borers in a Ponderosa Pine I'd brought home.  With the help of a bonsai teacher in our club I was able to save the tree with injections of Lindane.  I don't know if this insecticide is still available or legal.  Perhaps a web search will give you more information.   And bye the way I'm still battling sawflies on my mugo pine every spring which also must have come home on the ponderosa.  It's a matter of a spray of my homemade soap/alcohol/water every spring when they emerge from the ground.

Best of luck,  Norma

PS. The ponderosa was one of the bonsai stolen in 2000 from my yard.

This product should take care of him: Bayer Product with systemic insecticide.

I would do 2 things. Use the Lenz fumigation method but beforehand inject pesticide into the holes and plug or cover the holes.