Glossary E Flashcards
plant communities that first develop followinfg disturbance. Succession is the replacement of one plant community by another
early-successional plant communities
portion of an annual ring formed during the spring, characterized by large cells and thin walls, often lighter in color. Also called springwood. Contrast with latewood.
earlywood
drill bit with a wide, threaded shank used for drilling holes in the ground. See soil auger
earth auger
legal interest in real property that conveys use or partial use, but not ownership, of a portion of an owner’s property
easement
the study of the relationships between organisms and other living and non-living elements of their environment..
ecology
pest population or plant damage level at which the cost of inaction is less than the cost of action (see action threshold).
economic threshold
complex system of living organisms and their abiotic environment
ecosystem
the benefits people obtain from ecosystems
ecosystem services
type of mycorrhizae that grow between the cortical or epidermal cells of absorbing roots, forming an outer sheath around the root. See mycorrhizae. Contrast with endomycorrhizae
ectomycorrhizae
watery swelling in plant tissue
edema
EHS cable
extra-high-strength cable
conductors used to transmit electric energy and their necessary supporting or containing structures.
electric supply lines
corporation, person, agency, authority, or other legal entity or instrumentality aligned with distribution facilities for delivery of electric energy for use primarily by the public
electric utility
any object, material, or medium through which an electrical current can flow. Electric supply lines are designed as electrical conductors; however, guy wires, communication cables, tools, equipment, vehicles, humans, animals, and other items can function as electrical conductors.
electrical conductor
amount of electricity passing through an electrical conductor. Measured in amps
electrical current
difference in electric charge between an energized conductor and the ground or other object. Measured in volts.
electrical potential
relative opposition of an object, material, or medium to the flow of electrical current. Measured in ohms. Material such as copper has low resistance and is therefore a good conductor; material such as glass has high resistance and is therefore a good insulator.
electrical resistance
unintended redirection of electrical current to ground, interrupting the flow of electricity. If the path of an electrical short runs through a person, severe injury or death may result
electrical short
aerial platforms used on work sites in place of ladders and tower scaffolds
elevating work platform (EWP)
air bubbles in the xylem typically entering during periods of drought or injury.
embolism
rudimentary plant in the seed before it starts a period of rapid growth….
embryo
holes in the bark created by insects leaving the plant to complete their life-cycle. Also called exit holes.
emergence holes