4 Common Tree Diseases To Look for In The Pacific Northwest

June 25, 2019

As a local Tacoma tree service provider serving the Lakewood and Gig Harbor areas, we know a thing or two about trees here in the Pacific Northwest. In fact, we love just how different the trees that we get here in the Tacoma area are compared to trees in the Midwest and on the East Coast. 

While our trees are seemingly taller, denser, and much more covered in moss than trees in other regions of the United States, there are two major similarities between our trees and trees in other states. The first thing that our trees share with trees in other regions is that they need proper tree services like pruning and removal to be healthy, and the second is that our trees are just as susceptible to disease. 

When one of our customers searches “Lakewood tree removal,” there are usually two possible reasons that they do so. The two most common reasons that tree removal is necessary in the Lakewood, Tacoma, and Gig Harbor areas is because they are encroaching on buildings or because they have become diseased and are unable to recover. 

Much like humans, diseases can manifest themselves in the hardwood of our local trees — and if it is not caught in time, the tree will likely die. In order to avoid you having to contact us for dead tree removal, today’s blog post is dedicated to providing you with information that can potentially be used to diagnose a disease in your trees before they die!

Continue reading to learn about the four most common tree diseases in the Pacific Northwest. 

Phytophthora Root Rot

Caused by poor drainage and water around the base of a tree, Phytophthora Root Rot preys on the root’s inability to absorb the nutrients and moisture that it needs to survive from the soil.  Much like overwatering a houseplant, the roots beneath the tree will wither, rot, and later become a part of the soil once again. If the roots of a tree rot, they will no longer be able to support the tree, causing a fall hazard. If root rot is caught too late, the tree will have to be removed. If the drainage issues can be solved in the early stages of rot, however, it is possible that the tree might survive.

Affected Trees: Cherry, Dogwood, Holly, Madrone, Oak, Arborvitae, Cypress, Juniper, Cedars, Pines, Firs, & Fruit-Bearing Trees  

Verticillium Wilt

Fungal diseases are extremely common, here in the Pacific Northwest, due to the sustained high humidity of our climate. Verticillium Wilt lives in the soil and infects trees through their roots. As it spreads through the tree, it effectively shuts down the cells or the tree, forcing them to hold water and become infected. Common signs of Verticillium Wilt include the sudden wilting of multiple branches, a decline in new growth, and the yellowing of leaves. 

Affected Trees: Ash, Box elder, Oak, Linden, Walnut, Maple, & Other Hardwoods. 


Anthracnose is another common fungal disease in the Pacific Northwest. This fungal disease affects popular ornamental shade trees by infecting them and attacking the leaf system. Some of the most common symptoms of this fungal disease are curling leaves, spotting leaves, and early leaf drop. Keep an eye on your shade trees when winter weather starts to move in and wind and heavy cold rains occur, as this bolsters the disease’s strength. 

Affected Trees: Dogwood, London Plane, American Sycamore, Ash, Maple, Walnut, & Oak

Bronze Birch & Emerald Ash Borers

While they might not technically be a disease, pest infestations from a bug in the borer family can be just as detrimental to your trees. Both Bronze Birch and Emerald Ash Borer beetles bore into the wood of trees and feed on their interior tissues. In doing so, the tree loses its ability to transport water and other nutrients upwards towards the leaves and branches. Later, they lay their eggs in the tree and also consume the foliage — effectively killing the tree from the inside out. 

One of the most common signs that you have a borer infestation on your hands is that the canopy of the infected tree will begin to yellow. After a while, the branches will lose their leaves and the tree will be effectively dead. Other signs of infestation include holes in the bark, larvae beneath the bark, increased woodpecker presence and more. 

Affected Trees: Birch & Elm

Contact Our Lakewood Tree Service Specialists Today

If you suspect that any of your trees are infected with a disease of infested by a pest, we urge you to contact us before it is too late. If you notice any strange symptoms, fill out the form below and let us know what is going on! Then get your free tree treatment or removal quote. 

Tell Us About Your Tree’s Symptoms.