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Beech bark disease is a disease that causes mortality and defects in beech trees in the eastern United States, Canada and Europe. [ 1 ] [ 2 ] [ 3 ] In North America , the disease occurs after extensive bark invasion by Xylococculus betulae and the beech scale insect , Cryptococcus fagisuga . [ 4 ]
Trees have natural chemicals that keep most fungi at bay, but climate change could be making trees more vulnerable, researcher says.
Maple bark disease, or maple bark stripper’s disease, is an uncommon condition caused by exposure to the spores of C. corticale. [5] The spores are hyper-allergenic and cause a hypersensitivity pneumonitis. [6] [7] The disease has been found among workers in the paper industry employed to debark, cut and chip maple logs. The symptoms include ...
Where beech bark disease becomes established, most of the larger trees will die. Some trees seem to be partially resistant to the disease and a small number seem to be completely resistant. This may be partly due to the fact that trees with smooth bark provide fewer cracks and crevices in which the scale insect can flourish. [8] [9]
Early stages of the disease show a light brown and tan color that looks dry and dusty. Later on, as the pathogen goes through the sexual stage, the bark will turn to a dark grey color. The bark becomes brittle and flakes off, [2] and black and grey cankers will appear. [1] These changes are symptoms, indications of a disease.
Dutch elm disease was spread by elm bark beetles, yet the tree mortality was caused by a pathogen. [4] Chestnut blight is a fungus spread through wind dispersal and rain splatter; the blight traveled up to 50 miles in a year by natural means. [5] Insect pests, once they reach the adult phase, have the ability to disperse by flight.
The bark is a reddish black and gray and tinged with red or orange in the grooves; ... Heart rot is the only significant disease affecting black locust. [12]
These then enlarge to form cankers, which can then enlarge slightly more each year. The bark usually dies and can, after time, be pulled away from the tree. In older cankers the pycnidia appear on the bark. [1] Black dead arm disease of grapevine. Botryosphaeria obtusa is the pathogen of black dead arm disease of grapevine.