After having been inspected several times now for Anoplophora chinensis the following has appeared in my garden, in an apple tree. These are the exit holes, connected to tunnels in the heartwood. Each exit hole is about 1.5 cm in diameter, the entrance holes were small. The forestry fellow thinks this is not the villain, but he doesn't know what it is. He suggested perhaps it is Cossus cossus. Does anyone have any ideas? There were similar holes in an A. rubrum but I seem to have killed it by injecting insecticide into the passages.
Whenever I see damage like that, I fear the coming of the Asian Long-horned Beetle, but they tend to make a smaller and neater exit hole. Do you have Roundheaded appletree borer in your part of the world? Here is a link with a picture (see figure 2) of the damage they do to apple trees near the base of the tree. You need to scroll 1/4 way down the page to find the info on Roundheaded appletree borer. http://extension.missouri.edu/p/g7190
Well that's possible, and you're not the only one to suggest it. Not what the forestry department inspector thought though. This would be the first time I've ever seen woodpecker damage in the garden, although we sometimes hear them knocking in the woods. I'd be comforted to know the beastie bought the farm, anyway! :)
There is no doubt in my mind that that is woodpecker damage. Without seeing the larvae or galleries we can only guess at the identity of the insect the woodpecker is chasing, but if it was here in Ohio, USA I would suspect Flatheaded Apple tree Borer. Roundheaded appletree borer typically attacks just above the soil line on a tree that size.
