Ecosystem A system of plants, animals, and microorganisms interacting with their environment of soil, water, and climate.
Endangered species A plant or animal that is in danger of going extinct throughout all or part of its range.
Environment The prevailing conditions of climate, soil, topography, and biological (other plants and animals) factors in an area.
Epicormic branch A branch that develops by chance or from a dormant bud beneath the bark in an unusual location, usually on hardwood tree stems and major limbs. It typically arises after a stand has been heavily thinned, apparently in response to additional sunlight. Also called water sprout.
Even-aged stand A stand in which the age difference between trees forming the main canopy does not exceed 20 percent of the age of the stand at maturity.
Evergreen tree A tree that retains some or all of its leaves throughout the entire year, for example, red pine, white spruce, white-cedar.