Karen Tittaworth, age 10, of Rockford, ill., for her question:

What exactly is peat moss?

We buy bags of this lovely springy stuff and spread it on the ground to make the garden grow. This material is dead, dried peat moss. It was once a thick carpet of green growing mosses. Living peat moss likes moist, boggy soil and chances are it grew in or around an old lake. Many swamps and marshes and stretches of drowned land are clogged with layers of peat moss.

The top layer is often vivid green. Below it are other layers of dead, soggy mosses. Sometimes the swamp dr1e8 up and the land drains. Peop1e may then dig out the spongy old peat moss and use it instead of coal to make fires. If an old peat bog is left for millions of years, the ancient mosses may change into real coal.