Forest Pathology—Diseases in Washington State and their Management

Presented by Bob Edmonds. Forest diseases, mostly caused by fungi, are important components of natural forest ecosystems in Washington, causing tree mortality, producing snags and creating habitats for plants and animals, influencing forest succession, and recycling carbon and nutrients. Forest pathogens, fires and insects commonly act together. However, in managed forests they influence forest health, cause site degradation, kill planted trees, and cause economic losses. I will briefly describe the main diseases that occur along the I-90 corridor from Seattle to Ellensburg (the Mountains to Sound Greenway). This includes forest parks in Seattle, the leafy suburbs, State Forests, Parks, and Natural Resource Conservation areas, working forests managed by the Washington DNR and private companies, small woodlot owners, the now essentially unmanaged National Forests and recreation areas, and back to industry forests on the east slopes of the Cascades. Most of the diseases are native, but some are introduced such as white blister rust which has killed millions of 5-needle pine trees. I will also describe the disease management strategies on these lands which involve one or more of the following methods – silviculture (clearcutting, thinning, alternative species), chemical fungicides, biological control, and breeding and genetic resistance – as well as the consequences of doing nothing.

You will need to register to receive a link to attend the seminar via Zoom.

This seminar has been approved for one (1) WSDA Pesticide License Recertification Credit.

This seminar is part of our new Pesticide Recertification Seminar Series, which will include 11 opportunities to earn a recertification credit! Thank you to Lydia Tymon and Carol Miles for their work in organizing this.