Curtis Carroll, age 10, of Montgomery, Alabama, for his question:

What do toadstools grow from?

The toadstool we see is really just a package of seedlets. The main plant is out of sight, maybe hidden inside an old tree trunk or buried in soil that is mixed with old leaves and decaying plants. This part of the toadstool is a wad of pale threads called the mycelium. It hides out of sight in the shade because it needs a lot of moisture. The toadstool has no greenery to make its own food, as other plants do. So when those plants decay, the toadstool soaks up the chemical plant foods they made.

The hidden mycelium grows and spreads and at last the time comes to multiply. Then it sprouts up those stubby umbrellas we call toadstools. They are really fruiting bodies because the gill folds under the umbrella are stuffed with dusty seedlets, or spores. The matted mycelium must poke up the toadstools because it needs the breezes to scatter its dusty spores.