Localized diseased area on stems, roots, and branches. Often shrunken and discolored.
Open or closed hollow within a tree stem, usually associated with decay.
Forked stems nearly the same size in diameter, arising from a common junction and lacking a normal branch union.
Fruiting body or nonfruiting body (sterile conk) of a fungus. Often associated with decay.
An area of wood that is undergoing decomposition or the decomposition of organic tissues by fungi or bacteria.
Severe drying out. Dehydration
Condition in which the branches in the tree crown die from the tips toward the centre.
Fecal material and/or wood shavings produced by insects.
Reproductive structure of a fungus. The presence of certain species may indicate decay in a tree.
Abnormal swelling of plant tissues caused by gall wasps, mites, nematodes, and various insects and less commonly by fungi or bacteria.
Root that encircles all or part of the trunk of a tree or other roots and constricts the vascular tissue and inhibits secondary growth and the movement of water and photosynthesis.
Bark that becomes embedded in a crotch (union) between branch and trunk or between co-dominant stems. Causes a weak structure.
Any of various fungi of the genus Erysiphe that produce powdery conidia that appear as a white, fuzzy coating on the upper leaf surfaces, often causing distortion of the leaf.
Wood formed in leaning or crooked stems or on lower or upper sides of branches as a means of counteracting the effects of gravity.
Disease caused by a certain group of fungi and characterized by reddish brown spots on the foliage and/or the formation of stem galls
Compression of the soil, often as a result of vehicle or heavy-equipment traffic, that breaks down soil aggregates and reduces soil volume and total pore space, especially macropore space.
Fungus that appears as a black coating on the surface of leaves, fruits, branches, and other surfaces. Often found growing on sugary honeydew excreted by aphids
Factor that negatively affects the health of a plant; a factor that stimulates a response.
Tendency of growth or variation of a plant in response to an external stimulus such as gravity (geotropism) or light (phototropism)
The loss of turgor and subsequent drooping of leaves and young stems; a symptom or an infectious disease caused by a particular agent on a particular host or range of hosts.
Plant disorder characterized by a shortening of the internodes and a proliferation of terminal shoots forming a dense, brushlike mass of twigs.