The Point Arena-Stornetta Lands supports many different plant communities. There are large swaths of coastal scrub with coyote bush, huckleberry, and monkeyflower. Forested areas contain bishop pine, shore pine, and Monterey cypress. There is a surprising amount of wetlands and marshes with willow, red alder, and Humboldt Bay owl’s clover. Of all the plant communities found here, the coastal prairie played a vital role in the story about how these lands became federally protected.
Coastal prairie is a rare and unique plant community with tufted hairgrass, native bunchgrass, and a variety of wildflowers like the Douglas iris. The early blue violet is the larval host plant of the endangered Behren’s silverspot butterfly. These butterflies lay their eggs on the early blue violet, and the caterpillars feed on the plant’s leaves. Between July and early September, the adult butterflies spend their short 3-week life trying to reproduce and feeding on wildflower nectar. Some of its favorites are goldenrod, gum plant, yarrow, and seaside daisy.
Although early blue violets grow in many different environments in the west, the most critical habitat for the Behren’s butterfly is coastal prairie. Coastal prairies require regular disturbance to keep them from growing into scrubland and forests. Herds of elk once roamed this part of the coast, and their intense grazing helped create coastal prairies. Unfortunately, the elk disappeared because of overhunting right around the same time dairy farmers started grazing their livestock on this land in the late 1800s.
Although livestock grazing significantly impacted plant communities, it also kept the coastal prairie open. Now that the Point Arena-Stornetta Lands are part of the National Monument, the Bureau of Land Management works with local ranchers as part of a managed grazing plan.
Without coastal prairie, the Behren’s butterfly is likely to go extinct. Historically, the butterfly’s range was from the town of Mendocino down to Salt Point State Park, but its habitat is shrinking because of development, invasive plants, and overgrazing by livestock. As a result, the Point Arena-Stornetta Lands might be the butterflies’ best chance for survival.