by Cheryl Lowe

The Admiralty Inlet Preserve on Whidbey Island, a Natural Area Preserve (https://www.wclt.org/projects/admiralty-inlet-natural-area-preserve/), includes two rare prairie areas in addition to an amazing old-growth forest, three miles of walking trails with interpretive signs, and wonderful views of Puget Sound and the Olympic Mountains.

Less than 1 percent of Whidbey Island’s historic prairie habitat remains. For the last decade, the Whidbey Camano Land Trust (WCLT) has been restoring the prairie areas on this Preserve to help recover rare golden paintbrush (Castilleja levisecta) populations found here. The Land Trust has made enormous efforts to restore the population of this rare species, planting over 100,000 plants and using controlled burning techniques.

Western Washington prairies, a priority conservation habitat, are most often “dry prairies” found within the lowland regions of SW British Columbia and Puget Sound. As glaciers retreated more than 10,000 years ago, broad plains of glacial outwash, glacio-marine sediments, and alluvium were left behind. The porous gravels, in combination with localized climate effects, such as the rain shadows of coastal mountains, created conditions that favored open native grasslands with little or no tree cover.

Prairies, adapted to moist winters and dry summers, are typically located on these well-drained glacial soils. This fire-adapted habitat was historically maintained by Indigenous peoples who intentionally burned the prairies to prevent invading trees and shrubs from becoming established, increase the growth of food plants such as camas, and
improve habitat for game species. Fire suppression in more recent times has allowed for expanded growth of conifers and other woody plants in these open areas, crowding out native grasses and flowering plants of the prairies.