Scott Dickerson Jr., age 12, of Missoula, Mont., for his question:

ARE THERE MANY OAK SPECIES?

Oak is a common name of a large group of hardwood trees that are widespread in the north temperate zone. The oak genus contains about 450 species. About 60 different species can be found in the United States and Canada, and an additional 150 species are found in Mexico.

Oaks grow in a variety of habitats from seacoasts to high mountain slopes and from wet lowlands to high, dry mesas.

Flowering occurs in the spring, usually before the new leaves appear, and large quantities of pollen are often shed into the wind. The trees may be deciduous, losing most of their leaves in the fall, or they may be evergreen.

Most eastern U.S. species are deciduous    the live oak of the southeastern coastal plain being a notable exception    whereas the West has both evergreen and deciduous species.

Oaks produce durable, tough wood and are important lumber trees. The wood is used in cabinetry and barrel making and as flooring and veneers.

Oaks are distinguished from other trees by their distinctive fruit, the acorn.