Steptoe Butte Natural Area Preserve (dnr.wa.gov)

excerpt

Steptoe Butte Natural Area Preserve (NAP) was established in 2018 to protect the largest known remaining occurrence of Palouse prairie in Washington. With an estimated 2% of its historic range remaining, the Palouse prairie is considered one of the most endangered ecosystems in the continental United States. The 437-acre preserve was identified by the Washington State Natural Heritage Program for NAP status to protect four rare plants, four priority plant associations, and one rare earthworm species.