Mark Craze, age 8, of Spokane, Wash., for his question:

Does lightning really help the crops?

The plants feed on chemicals and they find their foods in the air and in the soil. They take oxygen and carbon dioxide gases from the air and a long list of chemical groceries from the ground. Some of their foods are gases and some are tiny solid fragments dissolved in water. One chemical they need is nitrogen and there is plenty of nitrogen gas in the air. But this is a gas that the plants cannot use.

In order to become useful plant food, the nitrogen gas must be changed into solid fragments. A seething flash of lightning forces nitrogen to combine with other molecules in the air. This creates new and different molecules. At last, after more changes, they are washed down with the rain into the soil. These chemical fragments are nitrogen compounds that the plants can use. The lightning adds plant food to the soil and really makes the crops grow.