Good or bad bug?
There are many different types of grubs. One or two is not a problem but if there are many then it is time to treat your grass or flowerbeds to get rid of them. These are the larva stage of beetles. They will feed on grass, roots and so on. If you have more than a few here or there, they will draw moles and armadillos to your landscape. Those critters will cause a mess in your lawn trying to find the grubs. If I see one while I am digging in my landscape, I just smush them--problem solved.
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