It depends on how much there is.

Recently, I've picked hazelnut enough to cover twice that table. I left plenty on the ground. Now, once the involucre, bad nuts and shells where remove, I have want cover a fifth of the table and got to share btw 10 house. Not that much. Plus hazel don't disapeare if you don't live some nut on the floor and I believe the underground part of the fungus either when you pick all the mushrooms.