Are cockchafers the problem? Or was it a stag party?

I was repotting a bunch of trees and plants this weekend when I made a nasty discovery!

I thought I had a cockchafer infestation, but now I wonder if maybe they were these bad boys:

Do any of you know anything about insects? I figured they were cockchafers and left them to the ravenous mynah birds who swooped down and ate them the minute I went inside.

If they were stag beetles though, I’d have preferred not to kill them.

From what I’ve read, stag’s don’t feed on roots though, which the larvas I found were defintely doing (all the trees were very stunted compared to the ones in grub-free pots.

Stag beetles don’t last very long as pets.

And here was me thinking this post was about too much starch in your underwear.
Anyway, if those beasties have already destroyed your plant, why not leave them there? When they hatch out, they’ll come out as those beautiful emerald green scarab beetles.
Stag beetle larvae eat leaf litter and rotten wood – not live roots.

Hmm… it all makes sense now.

These green scarab beetles have become such a big part of my life:

forumosa.com/taiwan/viewtopic.php?t=19307

I think I will let them be next time I discover them, one shriveled tree is worth the terror and entertainment these little guys provide.

[quote=“sandman”]And here was me thinking this post was about too much starch in your underwear.
Anyway, if those beasties have already destroyed your plant, why not leave them there? When they hatch out, they’ll come out as those beautiful emerald green scarab beetles.
Stag beetle larvae eat leaf litter and rotten wood – not live roots.[/quote]

Funny thing is that we call the Christmas beetles in Australia.