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Prairie Plant Inspection
Building permit applications for projects on prairie soils get on-site inspections for prairie plants, White Oak and Mima Mounds as part of the County's Critial Areas Ordinance (CAO). For 2020, the County is conducting "No-Contact" Inspections for your safety and ours. Find details in the "Gopher & Prairie Plant Inspection" info sheet (PDF). 

Prairie Plant Manual (PDF)    |     White Oak fact sheet (PDF)    |    Gopher & Prairie Plant fact sheet (PDF)    |    Prairie Soils & Gopher Soils list (PDF)   |    Prairie Plant List in the Critical Areas Ordinance (scroll down to tables 14 and 15)    |    Critical Areas Ordinance/Title 24    |    2020 Letter to Prairie Inspectors (PDF)    |    2020 Inspection Guidelines (PDF)    |    2020 Inspector Report Standards (PDF)

Basic review process 
  • On-site visits take place mid-April through mid-September, depending on weather (applications are accepted and prescreened year-round). 
  • Properites are visited one or two times, depending on site conditions.
  • Do not mow in the two-four weeks prior to inspection. Mowing may lead to reinspection, which could cause delays in processing your application.
  • An inspector walks the entire property looking for prairie plants, White Oak and Mima Mounds as listed in the CAO (linked above).
  • After the site visit, the project status is updated in the online permit status lookup, and the project case manager is notified. 
General prairie criteria
  • 3 or more CAO-listed prairie plants close together (about 16 feet). Or
  • 25 individual CAO listed plants or species on the project site. Or
  • Presence of plants that provide food or shelter for the Taylors checkerspot butterfly (a federally endangered species) or other protected butterfly species. Or
  • Presence of rare plants classified as such by Washington's Natural Heritage Program.
If prairie plants are found 
Some applicants modified their plans a bit to avoid mitigation requirements. Others applied for a Reasonable Use Exception. Others worked with prairie plant biologists to create a mitigation plan to replace prairie plants onsite that will be lost to the building project. Staff can discuss the options with you. All applications are processed in accordance with the County‚Äôs Critical Areas Ordinance.