Firstly, has the tree genuinely died, or are there still signs of life - such as green shoot tips? If the tree has died it may be beneficial to find out the cause of death. For example, if it is by fungal pathogen, it may be necessary to take immediate remedial action to stop its spread. A number of other factors may also have caused a rapid decline in health or the death of a tree, such as frost or lightning, chemical compounds and general poor management.
A common killer of garden trees is Honey Fungus, and it can be quite easy to spot this as sheets of white mycelium may be present under the dead bark, often with a strong smell of mushrooms. Black bootlaces (rhizomorphs) may also be present in the soil around the stem base and rooting. Honey fungus may kill a number of trees and shrubs in the vicinity and early detection can stop further problems occurring, although it should be noted that Honey Fungus may be present on or around a tree which has been killed or weakened by another agent. The fruiting bodies of Honey Fungus can also be easily identified - with a classic yellowy toadstool appearance when mature, and a ring or collar present on the toad stall stalk. These often do not last too long, particularly after frost, but still may be evident by a mass of blackened, mushy stalks on the ground. The best action in such cases is to completely remove the entire tree or shrub, including roots, with all of the material being burnt on site. Although this is not always possible and arrangements may be made to remove the affected branching and wood to a suitable site for disposal.