pH - acidity or alkalinity ranging from 3 (strongly acid) to 11 (strongly alkaline) with 7 being neutral.

The suppression of growth of one plant species by another due to the release of toxic substances.

Leaves that are staggered, not placed directly across from each other on the twig.

A group of fungi that cause dieback and sometimes death to various species, such as dogwoods, sycamores, oaks, and maples.

The flat part of a leaf or leaflet, characteristic of broadleaf trees.

A modified leaf that bears a flower.

A tree with leaves that are flat and thin, and generally shed annually.

the marks remaining after bud scales drop in the spring.