
Extensive native grasslands in North America are often called prairies. The grasses and wildflowers of Washington’s prairies are adapted to dry summers and gravelly soils left by retreating glaciers. For thousands of years before European settlement, Northwest indigenous people harvested the prairie's bounty of wildflowers and bulbs and regularly burned the prairies to keep them open.
Oak woodlands (or “oak savannahs”) and rocky balds are closely related habitats, sheltering many of the same species of plants and animals. In oak woodlands, the prairie grasses and wildflowers flourish under the open canopy of Garry oak trees (Quercus garryana). In rocky balds, prairie plants grow on shallow, rocky soils over bedrock, often on steep slopes. Rocky balds are most common in dry forest openings or on coastal bluffs.
North Puget Sound Prairies: Then and NowRemaining prairies will vanish without our help. Click map to see larger image.
The red areas on this map show all that remains of the prairies, oak woodlands and rocky balds in North Puget Sound. More than 98% of these habitats are gone. Fire suppression, converting land to agriculture and development, and growing numbers of invasive and exotic species all contribute to the destruction of these fragile ecosystems. We must act now to protect and restore what is left.
One of the rarest ecosystems in the country, these open savannas were created by retreating glaciers 15,000 years ago, which left behind gravelly soils that dried out quickly during summer droughts. Native Americans sustained these grassy plains for thousands of years using fire to keep the encroaching forests at bay so that tribes could harvest the prairie's bounty of wildflowers and bulbs. Today conservationists maintain our prairies through active management and restoration.