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Common Fungal Diseases on Evergreen Trees and Shrubs

There are many sources of fungal diseases that can cause an evergreen to appear sick or dying and greatly weaken the overall health of the evergreen trees and or shrubs. Treatments of these diseases often depends on the extent of the infection, the type of fungus, and the impact they will have in any particular landscape.

Plant diseases rarely kill the tree or shrub quickly. Fungal diseases make the plant sickly looking and unsightly. See photo - credit U.S. Forest Service. They weaken the overall vigor of the plant. And when disease infections are allowed to spread year after year their toll becomes evident as you can see a noticeable decline in the trees and shrubs health and beauty. Left uncared for your trees and shrubs will continue to decline to a condition of being unsightly or dead and that the only action at this point is for them to be removed.

Treatment Options

In terms of fungal infections many fungicide treatment methods work as a preventative but not as a means of killing existing infections. Early spring dormant and needle development stage treatments will help protect against new disease fungus outbreaks.

The use of Dormant Oil as well as other targeted insecticides should also be part of any plant disease managed care program. Homoptera insects, (such as aphids) feed on fungus and thus create yet another challenge for the trees over all vigor.

Some diseases such as "Root Rot" can seldom or ever be treated with any level of success. Once infected the only method of control is to remove so to avoid and minimize the disease spread or other plants in the general area.

Fungicide treatments can't do it alone. Proper pruning helps to prevent further spore spreading to healthy branches. Thinning of the tree or shrub helps to improve air flow, increases sun light and thus helps improve the plants overall vigor.

Since disease weaken the trees and shrubs vigor it is also in the best interest of your valued plants to be soil treated and deep root fertilized when and as needed. These treatments should not be applied until a qualified arborist has reviewed your particular landscape and assessed if the plants should be fertilized, with what method and type of material and when, (not all things are the same when it comes to fertilizing your trees and shrubs).

The goal for any tree and shrub is to keep them as healthy and beautiful as possible so we can all enjoy them. The mission of Branch Tree Service is to provide care and treatments which meet your needs.


For help identifying health care needs in your landscape please contact a professional arborist here at Branch Tree Service, Inc.


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