Glossary of Tree Terms

Kills living plant tissue.

Area of land which encompasses all of a plants roots. The root zone of a tree can can cover three times the distance measured between the tree trunk to the drip line.

Small insects from the insect order Homoptera that attach themselves to the underside of leaves and bark of trees and shrubs. They suck plant juices and can inject toxic saliva into trees and shrubs.

An advanced network of underground/above ground organisms containing bacteria, fungi, protozoa, nematodes, arthropods, animals and birds. These organisms gather nutrients such as nitrogen by breaking down organic matter. As one organism is consumed by another, a conversion of energy occurs making energy and nutrients available to plants and other organisms within the soil. The greater the diversity of organisms in the soil allows for more diversity of plants above ground.

Is a black mold that grows on leaf surfaces of plants which are covered with honeydew. The mold interferes with photosynthesis and is visually unappealing.

Tissues that function in the transportation of water, minerals, carbohydrates and other materials.

Not true flies, but small insects from the Homoptera insect order that suck plant juices (phloem) from the bottom of leaves. High populations cause leaves to shrivel, yellow and drop. The honeydew they produce may lead to sooty mold or sticky droplets on cars, sidewalks and driveways.

The plant vascular tissues that transport and store water and minerals from the soil into the tree. This tissue also serves as mechanical support by becoming heart wood when they no longer function as transportation.