I've found several of these grubs while gardening. Sometimes underneath my planters. What are they and should I be worried?

They look like the larvae of Scarab beetles. It's not possible to identify which Scarab beetle species from a photograph, they would need to be examined under magnification, but these are typical of the "white grubs" that damage lawns.

Beetle larva, agreed.

You need to look at the rastral pattern (pattern of setae) on the back side to identify to genus or species.

I just chuck 'em away from the garden. If they are the scarab beetles they help to remove dog poop...from dogs who visit the yard so they are a beneficial insect in my yard. If they were tiny they might be Japanese Beetles and I would...squash them like a bug.

sooby said:They look like the larvae of Scarab beetles. It's not possible to identify which Scarab beetle species from a photograph, they would need to be examined under magnification, but these are typical of the "white grubs" that damage lawns.

Not a scarab beetle after all. It's a Jerusalem cricket larvae.

That is not a cricket larva. Jerusalem crickets "Hatchlings resemble miniature adults and may take nearly two years to develop, while individuals experiencing nutritional deficiencies or parasitic infections may take up to five years. "
https://arthurevans.wordpress....

Look like a June bug larva to me.

GregC said:That is not a cricket larva. Jerusalem crickets "Hatchlings resemble miniature adults and may take nearly two years to develop, while individuals experiencing nutritional deficiencies or parasitic infections may take up to five years. "
https://arthurevans.wordpress....

We kept it in a container. Sort of like an ant farm and just yesterday the cricket was there, right at the top. Do you think it's possible we scooped up the cricket along with the dirt?

Too large. In our area, I'd say, Grape Pelidnota.

Yes, you must have scooped up both.

martham92 said:
...the cricket was there, right at the top.

After you saw the cricket, did you look for the larva to see if it was still in the dirt?

Philipwonel said:Look like a June bug larva to me.

greene said:

After you saw the cricket, did you look for the larva to see if it was still in the dirt?

I didn't exactly look for it, but I took the dirt out and reused it for seed germination and there was no more work, thats why I just asked it was a Jerusalem cricket