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An increasing number of people are interested in the outdoors. Many of these new enthusiasts have developed a keen appreciation for the great variety of wildflowers encountered on their sojourns. This … field guide has been prepared to help naturalists, hikers, campers, and botanists recognize some of the numerous wildflowers seen on the trails, back roads, and parks in the south-central Pacific Northwest.

The field guide covers a region broadly known as the Southern Interior (see map). It stretches from the Cascade Mountains in the west to the Alberta border in the east; from the Trans-Canada Highway in the north to roughly the 45th parallel (through Washington, Idaho, and Montana) in the south. Within this region a myriad of wildflowers colour the meadows, hillsides, and woodlands.

The Southern Interior region is geographically diverse and, accordingly, the area’s flora varies dramatically with changes in climate, soils, topography, and elevation. These factors separate the vegetation into zones representing elevational bands across the mountainsides and valleys. Seven zones have been described for the Southern Interior.

At lower elevations in the drier areas the Bunchgrass, Ponderosa Pine, and Interior Douglas fir zones predominate. The Montane Spruce zone occurs on upland slopes at mid-elevations. At higher elevations, occupying the forested areas, is the Englemann Spuce-Subalpine fir zone. The Alpine Tundra zone is found above the treeline. In moister areas, at lower elevations, the Interior Cedar Hemlock zone is evident.

A starting point for the amateur enthusiast would be to learn to recognize tree species, which aid in determining the zone. Usually specific plant communities are associated with different zones. For example, Arrow-leaved Balsamroot and Big Basin Sagebrush are characteristic plants of the Bunchgrass zone, whereas the herbs Sitka Valerian and Simple-stemmed Twistedstalk are found at higher elevations in the Englemann Spruce-Subalpine fir zone. Therefore, understanding the relationships between zones and vegetation will aid in finding new flowers as well as in learning to recognize unfamiliar ones.

The field guide describes 335 species, each with an accompanying colour photograph for quick and easy identification. The wildflowers identified and described include: (a) the most showy, familiar or common plants encountered in the region; (b) alien and “weedy” plants that have become well established in the area. The enthusiast is thus provided with the knowledge to identify a wide range of flowers and to note where man has changed the look of the wilderness landscape. Included in the flowering plants are a few smaller flowering shrubs. Trees, ferns, grasses, horsetails, sedges, and rushes have not been described.

Enjoyment of wilderness landscapes is based on aesthetic appreciation and factual information. This field guide will augment the former and strengthen the latter. Enjoy these beautiful flowers.
Carol E. Thompson