Tony Bouknight, age 9, of Lexington, S.C., for his question:

What is mold?

A patch of mold or mildew is really a harden of tiny plants, too small for our eyes to see. They are fungus plants, cousins of the mushrooms and the toadstools. There are countless numbers of different molds and mildews and most of them live in the soil. There they do a wonderful job, making the soil richer to feed the larger plants. Lets remember this next time a patch of green, grey or blue mold spoils the cheese or a slice of stale bread.

When magnified, we see that a patch of mold is very neat and lovely. Each miniature plant stands on its own little stalk. Some are crowned with spikey little knobs, some seem to end in fluffy foliage and some fan out into ferny froth.