Gills

Choose this category if you aren't sure, the underside is smooth-ish, or if it's difficult to tell what's going on under there.

Pores

Little holes that make a surface somewhat like a sponge.

Ground-dwelling mushrooms in this category are Mutualists with nearby trees, especially oaks and pines. They may be members of the genera Sarcodon, Hydnum, or Hydnellum.