There are at least three species of morels in Missouri. All are hollow-stemmed mushrooms emerging from the ground in spring to early summer, with a somewhat conical cap/head covered with definite pits and ridges, resembling a sponge, pinecone, or honeycomb. In black and yellow morels, the bottom of the head is attached directly to the stem. In half-free morels, the bottom half of the cap hangs free from the stalk. In all cases, the stem of true morels is hollow.
Look-alikes: Don't confuse true morels (Morchella spp.) with false morels (Gyromitra spp.), which can kill you. Don't eat any wild mushroom unless you've identified it as a safe edible and have cooked it thoroughly.