Home About edenarb Contracting Contact Details - Tree Basics Leaves Branches & Trunk Root Systems Health CODIT Leaves Trunk & Branches Root System Structural Care Tools Hand Power Safety Pruning Formative Small Branch Large Branch Advanced Selection Planting Identification Native UK Trees Environment Legislation Photo Gallery EDENARB Trees Miscellaneous Credits Links   The Trunk & Branches   Fungi   Fruit bodies of certain fungi are often known as conks. There presence is a sure sign of decay within the tree. We can also gain more knowledge by there shape and growth pattern.     There may often be a series of conks growing in a line. If the size of these goes from small at the base to large at a higher level then the decay is working down the tree, likewise they are larger at a lower level and decrease in size then the decay is spreading upward from its original source. The shape and condition of the fungi can also be used as an indicator to the degree of decay. If the growth increments of the fruiting body are still large it is possible that there is still a lot of sound wood, but if these increments are getting smaller then the likelihood is that the decay may becoming more substantial.   It is essential that visible fungi on or around a tree should always investigated by a competent person.   Cavities   As with fungi if there is evidence of a cavity on a tree it should always be investigated by a competent person. A lot of cavities are easily visible but some are more inconspicuous. Use common sense to imagine where a cavity may be likely to form (i.e. between a tight crotch) and keep an eye out for weeping, darkening of bark or fungi. Check around the base of the tree and buttress roots for frass (fine sawdust and insect excrement) which can indicate decay.   Fractures & Twisting   It is possible to get fractures caused by stresses (such as tension and shear) that do not fail immediately. These may only be visible upon close inspection if at all. Be wary of a branch system that shows characteristics that are not in common with the rest of the tree. Bursting of the bark and ribs along the bark are indicators of the presence of internal fractures. Twisting is generally a growth defect but the resultant trunk or branch may be more susceptible to failure. The risk of fracture and twisting varies with species/location and form.     Included Bark   If a tight crotch forms the bark becomes trapped as the tree continues to grow. There will be no new growth attachment above the crotch and therefore the point of attachment will be weak, this also creates an environment likely for decay. The hazard and risks associated with included bark can be reduced by correct formative pruning.