Design - Roadside and Site Development - Vegetation Resources

Old Growth Conifer Forest
Stand of mature/growth conifer forest near I-90

Vegetation Restoration Concepts
Chapter 810 of the Roadside Manual (pdf 510 mb) contains guidelines that provide the background for the development of effective vegetation restoration methodologies. Two basic restoration approaches are used: managed succession and accelerated climax community development. They are based on the principles of plant succession in natural ecosystems.

It is the policy of WSDOT to use native plants. This map of Washington State Eco-regions is an aid in determining what is considered native, and may be used to help in specifying and obtaining plant materials.

Eco-regions denote areas within which ecosystems (the type, quality, and quantity of environmental conditions) are generally similar. The approach used to compile this map is based on the premise that ecological regions can be identified through the analysis of the patterns and the composition of biotic and abiotic phenomena that affect or reflect differences in ecosystem quality and integrity (Wiken 1986; Omernik 1987, 1995). These phenomena include geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another regardless of the hierarchical level. 
Vegetation Alteration
Neighbors and businesses adjacent to WSDOT right-of-way often request to alter, remove, or even plant trees, shrubs, and plants on WSDOT property. WSDOT works with others to plant on our property; however, WSDOT policies do not support requests for removal or alteration of vegetation. There may be rare exceptions that vegetation alteration may be allowed if it is mutually beneficial to the goals of the transportation facility. The following lists the policies and procedures (pdf 282 kb) evaluate these requests.





Juli Hartwig, PLA
Roadside and Site Development Manager
Phone: (360) 705-7242