Numerous species of fungi can affect evergreen trees, most of which require their own unique methods for treatment and control. Some of the more common problems and diseases caused by evergreen fungi include root rot, blight, cankers, needle cast disease and rust.
Fungal cankers are one of the more widespread types of evergreen diseases, which are caused by an internal infection of any one of several different species of fungi. These cankers are areas of dead bark that are usually visible due to the sticky, white resin that leaks out of them. The fungus causes the death of the bark, which leads to the surrounding area dying and losing its needles, commonly known as needle cast disease. This disease only affects trees that are stressed by other environmental factors and can usually be treated by aerating and fertilizing the area around the tree.
If the tree has a rust or blight type of fungus, the only effective treatment method is to spray it with an approved fungicide. If the tree suffers from a root rot fungus, it is likely related to improper draining of the soil. Fungicide may help in such a case, but first it is necessary to solve the excess water problem to prevent the infection from returning.