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Prairie Plant Inspection

2021 Prairie Plant Inspections are Underway Now


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). The County is conducting "No-Contact" Inspections for your safety and ours. Find details in the "Gopher & Prairie Plant Inspection" info sheet (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.
  • Follow mowing requirements (PDF) carefully so ground is visible. No mowing three weeks before inspection. Mowing may lead to reinspection, which could cause delays in processing your application.
  • Don’t dig, move dirt, pull stumps, add gravel or level mounds until AFTER project is permitted.
  • 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’s Critical Areas Ordinance.