In my compost is a large grub like thing. I first saw
it when I had to compost dug out about three weeks ago and it was large like a swollen up cutworm. Today I distributed my black gold and found it and it is huge! About 2-1/2 inches long with a diameter of at least 1/2 inch or more. I have only one. I put it in a deep large saucer and after adjusting to the surrounds it made rather quick circles around the edge. I then covered it with a little compost and it calmed down, although it has emerged and circled again. It is light brownish to grey and seems to have a couple of little moving parts on the upper side that it doesn't use for locomotion. It scoots along, best analogy is like a worm although it is total forward direction.

Gardener insists it is beneficial. I am not so sure.
But in case I am wrong I don't want to destroy. Looks almost as ugly as a potato bug, but aside from ugliness doesn't resemble a potato bug in any other way.

Please help me identify whether it is beneficial or not and if I should let it loose or destroy. Thanks! Michelle

You could put it in a more secure but ventilated container with compost and see what it turns into.

Perhaps an asparagus spear being carried around by a family of ants? :-) Can't say it sounds familiar though. I thought I 've had my share of grubs and worms, but none ever seem to get that big. The only thing that comes to mind is something like a hornworm. Best of luck determining both its identity and its intention.

i have these too. no idea what they are.... like huge grubs. sometimes i find them a foot underground. always in high humus content, like my compost. but i don't think they're beneficial.

Yup, that's him. But what exactly is this monster grub?

I know what this is, just can't remember the name. It is the grub of those green flying beetles that appear in the summer and eat tomatoes and figs. (I'm not guessing, there have been articles about them in the LA Times.) They won't hurt the compost, probably aerates it, but because they eat fruit, whenever I find any I put them in a bowl and leave them out for the mockingbirds and bluejays. The birds always ask for the grubs, and eat them immediately. Since I began killing the grubs this way there are far fewer of the flying beetles.

That's consisent with what I found in some pictures I was looking at today. I think it was Japanese beetles, but I'm not sure. Unless someone convinces me soon this guy is beneficial I am going to follow your lead just after I show this litle speed demon to my grandson in the morning. He runs around the saucer (assuming he is still there) lie a hamster in a habit trail.
Thanks! Michelle

Eww! Japanese chafer beetle grub! If you got chickens, give him to them...they love em. I kill them when I find them...which isn't often since I started using predatory nematodes and milky spore