Wildflowers of Unalaska Island-A Guide to the Flowering Plants o

The Aleutian Floral Region

Eric Hultén, renowned authority on arctic plants, distinguished four major fl oral regions in Alaska, yet wrote, “The Aleutian Islands should perhaps be regarded as a fi fth fl oral region” (Hultén 1968). Strewn like seeds in the wind, Alaska’s Aleutian Islands are fl ung out into the stormy North Pacific for eleven hundred miles. The islands break the seas as a spine of volcanic mountains, hemming in the Bering Sea to the north, and reaching in an arc between western North America and eastern Asia. Rugged, windswept, cold and wet, these islands possess a unique vegetation unlike any other on Earth. A thousand miles below the Arctic Circle, the central Aleutians dip farther south than any point in heavily forested southeastern Alaska, yet the islands are a region of treeless tundra.

Throughout the winter months, the islands lie bleak and barren, but in summer a deep green cloaks the hills. Compared with the rest of Alaska, the temperatures are moderate, and the wet maritime climate yields lush plant growth, especially near sea level. While the Aleutians lack mainland Alaska’s subzero temperatures and permafrost, they also lack the brief intense warmth of the mainland summers. There is truth to the local quip that we have two seasons here: winter and spring. Mean annual temperature
is around 40° F. The only months usually free from a frost at sea level are June, July, and August, and few August days warm above 70° F. By September, the fall gales have begun their long marches across the chain, and the ground cover smolders crimson and ruddy orange beneath the lashing rains. Though temperatures in the coldest winter spells seldom drop below +10° F, the Aleutians are notoriously stormwracked. Low pressure systems sweeping over the Bering Sea bring months of intermittent blizzards and freezing rain. Yet there thrives in the Aleutians a sturdy and diverse world of plants.

So many questions begin to unfold as one studies the life of plants in such a place. Where did they come from? How did they get here? How long have they been here? To consider these things necessitates a brief look back in time, though, in truth, this may reveal more questions than answers. In the Aleutians, much remains a mystery as our knowledge is incomplete; the remaining questions are fascinating and well deserve further study.