Thick green grasses, hearty shrubs, white wispy cotton grass, and patches of purple, pink, blue and yellow flowers all turning their petals toward the sun—this is the Alaskan tundra that greets scientists and visitors to the Toolik Field Station during the summer field season. While winters are bleak and stark white, the summer conditions on the tundra bring a welcome, and colorful, change in scenery.
After months of wind, snowstorms and freezing temperatures, the area surrounding the Toolik Field Station, situated in the northern foothills of Alaska’s Brooks Range, is dotted with colorful plant life. Plants like the bright yellow Arctic poppy and the brilliant purplish-blue Arctic lupine are putting on a short-lived display.
Beginning in June, the rising temperatures coupled with near 24-hour sunlight start to thaw the very top layer of the permafrost, known as the active layer. (Permafrost is soil that has been frozen for two or more years.)
Anja Kade, a scientist with the University of Alaska Fairbanks Institute of Arctic Biology and instructor at the field station, points out that soils in permafrost-affected areas are often quite nutrient-poor and waterlogged. As the top few inches of the soil thaw, the portions underneath remain frozen allowing little or no drainage. The result is a very soggy top layer of permafrost soil. “We usually need boots to walk around out there,” Kade said.
The region’s hearty plants have evolved to thrive in these conditions. Two types of tundra are typically found around the Toolik Field Station: the very moist and spongy tussock tundra and the much drier heath tundra. Each supports different plant life.
A stroll through tussock tundra reveals thick clumps of white Arctic cotton grass, green mosses, lichens and vascular plants. This type of tundra is often called “ankle breaking tundra” due to the thick tussocks (or clumps of cotton grass) that make the ground underneath feel very spongy, Kade explained. There are also many blooming plants like the Arctic lupine, the yellow and white Arctic dryad and various species of lousewort that produce blooms ranging in color from yellow to pink.
Heath tundra is another common tundra type near Toolik. Kade described it as much drier and less vegetated than tussock tundra. “Dry heath tundra usually supports more lichens along with the typical heath species such as cranberry and blueberry,” she said.
Many of the plants at such high latitudes are much smaller than those found in a more temperate climate. For instance, rhododendrons top out at only four inches tall.
There are also several species of shrubs, including dwarf birch and willow that usually grow no more than three feet tall. “Summers are too short to allow for much wood production and there may be sun for only two months,” Kade said. In late August and early September the shrubs will begin to change color. The display of colors is much like one would expect in the northeastern regions of the United States, just on a much smaller scale.
Summer doesn’t last very long on Alaska’s tundra. As September comes to a close, though daylight lingers, the colors on the tundra surrounding the field station are mostly gone. But in a year’s time, they’ll be back.
"It is nice, after the cold days of winter, to see little bursts of color on the tundra,” Kade said. “It makes you feel happy.”
For more information about the Institute of the Arctic’s Toolik Field Station and ongoing research projects there, visit http://toolik.alaska.edu/