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This is a glossary of words that relate to electricity and trees. Many of these words are used in the SafeTree website and/or in the SafeTree booklet.

Amperage, amps
A measurement of the amount of electric current.

The smallest unit of matter. Scientists so far have found 112 different kinds of atoms. Everything in the world is made of different combinations of these atoms.

The outer covering of a tree that protects it from bad weather, fire, insects, and fungi.

A thin layer of cells inside a tree that produce phloem on one side and sapwood on the other.

A closed loop of conductors that allows current to flow from a power source and back.

Something that allows electricity to flow through it easily. Water and most metals are good conductors. The reason conductors allow electricity to flow through them is because the electrons in their atoms move between atoms very easily.

The movement or flow of electricity.

The science of tree rings.

Distribution lines
Power lines that carry electricity through neighborhoods to homes and businesses. Distribution lines can run overhead or underground.

The flow of electrons.

The basic particle that orbits the nucleus of an atom. The flow of electrons produces electricity.

The ability to do work. People get energy from food. Your toaster and your washing machine get their energy from electricity.

Everything that surrounds and affects living beings.

A machine that converts mechanical energy into electrical energy.

Old cells inside a tree that give it strength.

Something that does not allow electricity to flow through it easily. Glass and special rubber are good insulators. The reason insulators do not allow electricity to flow through them easily is because the electrons in their atoms do not move from atom to atom very easily.

The inner bark of a tree that moves sap down from the leaves to all the parts of a tree.

The process by which trees and green plants capture the sun's energy and turn it into glucose, the fuel the tree or plant needs to grow. In the process, carbon dioxide is absorbed from the air and oxygen is given off.

The central core of a tree.

Power plant
A place where electricity is generated.

Power line
A wire used to carry electricity. Power lines are located high overhead or buried underground.

The younger wood of a tree through which the raw sap rises from the roots to the leaves.

Service drop
The wire that carries electricity from a power pole to a building.

A facility where transformers lower electricity's voltage.

A device used to increase or decrease electricity's voltage.

Transmission lines
Power lines that carry high-voltage electricity long distances.

Underground lines
Power lines that are buried beneath the ground.

A company or other organization that provides a public service, such as supplying electricity, natural gas, or water.

Voltage, volts
A measure of the pressure under which electricity flows.

Wattage, watts
A measure of the amount of work done by a certain amount or amperage of electric current at a certain pressure or voltage.

The part of a tree that carries water from the roots up to the leaves and
forms the wood of the tree.