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Taphrina caerulescens is a species of fungus in the family Taphrinaceae. It is a pathogenic Ascomycete fungus that causes oak leaf blister disease on various species of oak trees (Quercus spp.). The associated anamorph species is Lalaria coccinea, described in 1990. [2] This disease causes lesions and blisters on Oak leaves.
Oak wilt is a devastating exotic disease, killing some trees rapidly in a single season. [7] Oak wilt is an important disease in urban areas where trees are highly valued. . The disease reduces property values because of the loss of trees and is economically costly to the property owner since they or the local government must pay for tree remo
Cystotheca lanestris, the live oak witch's broom fungus, is a species of mildew that infects buds and induces stem galls called witch's brooms on oak trees in California, Arizona, and Mexico in North America. [2] [3] Witch's brooms are "abnormal clusters of shoots that are thickened, elongated, and highly branched."
Only young developing leaves are susceptible to colonisation by E. alphitoides.It only induces necrosis when infection occurs very early during leaf development. Because the pathogen develops late in spring, after the first leaves of oak seedlings have developed, it is more prevalent on the second and third flushes of leaves that develop in July and August.
Oak wilt is a fungal caused by Bretziella fagacearum, is a disease originating in eastern Russia. It can slowly or quickly kill an oak tree when the tree reacts to the fungus by plugging its own cambial tissue while attempting to block the spread of the fungus. This plug prevents the cambium vascular tissue from delivering nutrients and water ...
Leaf (adaxial) of bur oak infected by BOB Leaf (adaxial) of bur oak infected by BOB. When affected by the disease, the oak develops vein necrosis confined to the leaf midvein and major lateral veins, eventually causing leaf death. Symptoms typically start in the lower crown of the tree and eventually spread to the entire tree. [3]
The disease kills oak and other species of trees and has had devastating effects on the oak populations in California and Oregon, as well as being present in Europe. Symptoms include bleeding cankers on the tree's trunk and dieback of the foliage , in many cases leading to the death of the tree.
The common spangle gall on the underside of leaves and the currant gall on the male catkins or occasionally the leaves, develop as chemically induced distortions on pedunculate oak (Quercus robur), or sessile oak (Quercus petraea) trees, caused by the cynipid wasp [1] Neuroterus quercusbaccarum which has both agamic and bisexual generations.