Chapter 7 Key Terms

fall line

imaginary line between the appalachian mountains and the atlantic coastal plains.

growing season

in farming, the average number of days between the last frost of spring and first frost of fall.

humus

the organic material that results when plants and animalsthat live in the soil die and decay

sunbelt

the southern and southwestern states of the United States from the Carolinas to southern California , characterized by a warm climate and, rapid population growth.

tundra

a dry treeless plain, where temperatures are always cool or cold and only specialized plants can grow.

aqueduct

a large pipe or channel designed to transport water from a remote source over a long time

bayou

a marshy inlet or outlet of a lake or river

grain exchange

a place where grain is bought and sold as a commodity

grain elevator

a tall building, equipped for loading, cleaning, and discharging grain

mangrove

a tropical tree that grows in swampy ground along coastal areas

megalopolis

a very large city; a region made up of several large cities and their surrounding areas