Does anyone know what this is? I found it today in my basil/ tomato bed. Some attatched to roots of some basil, and some just in the soil. They're pretty solid pieces, the little balls are about the size of peppercorns. And when I dug that out there was gray, carboard like stuff... Any clue on what it might be? And how to get rid of it? Will it hurt my plants if I can't get rid of it?
Lone ball of whateveritis.

Attatched to what used to be basil..

HELP!!
Lone ball of whateveritis.
Attatched to what used to be basil..
HELP!!