Is this a dead borer on my albizia?

I found this dead insect embedded in the trunk of my A. julibrissin. This is how I found it, with its rear sticking out of the hole it had made.
Is it a borer?

Here it is just after I've pulled it out, leaving part of its head still inside the trunk.

Close up.
So, is it a borer? Should I be worried?

Hi, you have a moth pupa case.
I get them coming out of the lawn now and then, just before it rains.

Borers are usually beetles and wasp larvae, and sometimes moths
Common borers
http://www.dpi.qld.gov.au/4790_14056.htm
More info here
http://entomology.unl.edu/ornamentals/pestprofiles/roundheaded_borers.shtml

If you are seeing the case the bug has already gone thru its life cycle.

This is a moth pupa from the lawn
http://www.flickr.com/photos/arthur_chapman/4568781729/

I think it would be impossible to track down what exact bug it is but if you have the time you can flick thru this page

Australian Moths Online
http://www1.ala.org.au/gallery2/v/Hepialidae/

Sadly, I've done some more research and it is almost certainly a borer, the Albizia borer aka Xystrocera festiva.
I'll have to think about what to do, as there are two sites on the tree, both of them on the trunk--one near the ground and so impossible to prune off. I know albizias are short-lived and I do now remember that they are susceptible to borers, so I might have to remove it when I take out a couple of other trees. Stressed trees are supposed to be most susceptible but my tree looks healthy.

Strange things are happening in your garden, cestrum....are you sure that one did have a head...LOL

I've seen borer holes in trees but never spotted the culprits...

You poke a piece of wire into the hole and wriggle it around then block the exit with softened soap is what I do.
I hope the tree is ok.

The tree's days are numbered, alas. I saw those two holes near ground level because I was weeding (and so focused at ground level), but I had another look today and there are more holes--including at least one with the dead insect sticking out of it--on the higher branches. So it will have to go out ... but maybe not until autumn/winter, so that I can enjoy the blooms and the summer foliage. I think I might have to just plant a frangipani there.

PS I can post you the insect carcass if you want to see it yourself, Dianne ;-)

This message was edited Oct 21, 2011 3:20 PM