Donna Carter, age 10, of Marquette, Mich., for her question:

ARE THERE MANY KINDS OF CLOVER?

Clover, a plant that you'll find growing wild in fields, on lawns and along roadways, come in about 300 different varieties. Several kinds of the plants are cultivated as food for livestock.

All of the clovers are legumes, which means that they belong to the pea family. They usually have three leaves in a cluster, but sometimes they have more. Some people believe that four leaf clovers can bring them good luck.

You'll find most of the clovers growing in the Northern temperate zone, although some of them are also found in South Africa and South America. The plants grow successfully in lowlands and also high up in the mountains.

Most important of all the clovers is red clover. It is called a weak perennial, which means that it lives two or more years. It grows from 6 inches to about 2 feet tall. Farmers grow red clover to make hay, to offer pasture food for their grazing farm animals and to help enrich the soil of their fields.

Red clover plants can actually take nitrogen from the air by means of bacteria growing on their roots. Then when the plant is later plowed under, the nitrogen helps make the soil richer.

Many people don't realize that about five times as much red clover as alfalfa is grown in the United States each year to feed livestock.

Red clover flowers usually will not be fertilized unless bumblebees pollinate them. When red clover was first planted in Australia, there were no bumblebees to carry the pollen. Not until bumblebees were introduced into the country would the red clover produce seed.

Alsike clover is often called Swedish clover. It came to America from Sweden by way of England. It grows well in cool, moist climates.

Crimson clover is often used for soil improvement and for livestock feed. Its flowers are often red, but sometimes may be white or yellow. Crimson clover must be planted from seed every year. It has often been called scarlet or Italian clover.

Other clovers include hop clover, rabbit foot clover, Ladino clover, mammoth red clover, medicago and strawberry clover. Another one is Japan clover, which is best known as lespedeza.

White clover does not grow tall. Its stems creep along the surface of the ground and send down roots. For this reason, white clover spreads rapidly and provides an especially valuable plant for pastures and lawns.

Sweet clover is not a true clover, although it is a legume. Sweet clover plants are tall, erect plants and are somewhat like alfalfa in appearance. White and yellow sweet clovers, which live for two years, are widely grown in the southwestern states. Their large roots penetrate deep into the soil. At the end of their second season, they decay and enrich the soil with nitrogen and decaying vegetable minerals.

Sour clover, a kind of sweet clover used almost entirely to improve the soil, is often called melilot.