phase of site development that provides a site with intended grades (contours, elevations, and slopes). Involves cutting and filling. See mass grading.

sheet of a complete set of development plans that depicts both original and finished (changed) grades. Essential information in developing tree conservation or preservation plans.

to join together tissues from the same or different plants in order to combine desirable characteristics or to effect a repair (bridge graft).

junction between root stock and scion wood. Often evident by a thickening of the trunk at the union.

water that drains from the larger soil macropores due to the force of gravity. Compare to available water, field capacity, permanent wilting point, and saturation point.

acronym for Good Rigging Control System, the brand name of a friction device used in rigging.

mulch composed of green (rather than woody) organic matter and not fully composted or decomposed. Also cut or mowed herbaceous material (grasses, etc.) that are left to decompose naturally and improve the underlying soil quality.

(1) the earth

metal rod used in grounding a tree lightning protection system.

in utility arboriculture, the distance between live or energized conductors and the ground. In the United States, these clearances are specified in the National Electrical Safety Code.

electrically connected to the earth, properly providing a path for the flow of electricity to prevent accidental energizing.

water naturally stored underground in aquifers or that flows through and saturates soil and rock, supplying springs and wells.

speed at which something grows.

rings of xylem that are visible in a cross section of the stem, branches, and roots of some trees. In temperate zones, the rings typically represent one year of growth and are sometimes referred to as annual rings.

pair of specialized cells that regulate the opening and closing of a stomate (see stomata) due to a change in water pressure within cells.

exudation of sap or gum from the bark, often in response to disease or insect damage.

(1) a steel or synthetic-fiber cable between a tree or branch and an external anchor (another tree, the ground, or other fixed object) to provide supplemental support. (2) a steel cable between a utility pole and an external anchor (another pole, the ground, or other fixed object, which may sometimes be a tree) to keep the pole upright. Guys act in tension. Contrast with prop.

installing a guy and associated anchor.

plants with exposed seeds, usually within cones. Contrast with angiosperm.

hydrated calcium sulfate. Sometimes recommended as a soil conditioner or a source of calcium.