Subject: What is this
Geographic location of the bug: Montreal , Quebec
Time: 07:06 PM EDT
Your letter to the bugman: We found this on a diseased Maple tree in our backyard. Can you identify what this is
How you want your letter signed: Alan Kelly
This is a female Giant Ichneumon in the genus Megarhyssa, probably Megarhyssa macrurus which is pictured on BugGuide, and she is ovipositing or laying eggs. Since you have indicated that your maple tree is diseased, it is most likely infested by various wood boring insects, including the larvae of the Pigeon Horntail, the prey of the Giant Ichneumon. The female Giant Ichneumon senses the presence of the larval Pigeon Horntail burrowing in the wood, and she inserts her long ovipositor so she can lay an egg on or near the larval Horntail. When the egg hatches, the larval Giant Ichneumon will parasitize the Pigeon Horntail larva. The Giant Ichneumon will not harm your tree.