Monday, April 9, 2012

Carbon Sequestration in Sagebrush Steppe

Friends of mine called the drive from Boise to Mountain Home, ID, “The Big Ugly.” The one who wasn't driving tried to be asleep by the time they passed the outlet mall on the eastern fringe of Boise. The sleeping friend didn’t have to see the expanses of exotic, invasive cheatgrass that dominate the 40-mile stretch.

This grass was able to invade after the native vegetation was killed by the fires that splash blackened smudges across the area most summers. Green for only a few weeks in spring, cheatgrass spends most of its life as a blanket of short, brown stems, leaves, and bristled seeds. The seeds attach to your socks and work their way down into your boots. They use their travelling tricks to spread into other areas where the native plants have been killed or weakened, where they take root.

My friends had lived in Boise long enough that they remembered when the trip east out of Boise was lush with a shrub forest of sagebrush, tall native bunchgrasses, and evanescent wildflowers in spring. The varied plants wove a tapestry of different shades of green that woke up from winter in waves: first the bluegrass, then the squirrel tail, then the needlegrass and wheatgrass filled the areas between the shrubs. The forbs took turns showing off. Some years the balsamroot astonished my friends with washes of yellow across the hills. Other years the lupines gave it their all and created a pointillist painting with touches of blue. On some trips the red paintbrushes shone and other times it was the yellow ones.

My friends lived next door to each other and worked together for years; they knew each other's stories. But the sagebrush and grasses and wildflowers spun them a new tale each time they traveled to Mountain Home and beyond.

In addition to entertaining my friends, the native sagebrush vegetation also did a far better job of capturing and sequestering carbon dioxide than the carpet of cheatgrass now does. The Big Ugly contains much less carbon in its soil than it did previously, researchers from Boise State University have found.

You can learn more about the study in a piece I wrote for BSU’s Division of Research and Economic Development.


  1. We are surrounded by beautiful sage, often called grandfather sage. I am curious about its ability to capture carbon

  2. Great question. Sagebrush steppe definitely sequesters carbon; here's one of several studies - . And sagebrush stands definitely store more carbon than cheatgrass stands. . Sagebrush does other things for us, too. Sagebrush uses deep water, so that exotic invasive perennial forbs such as knapweeds have a hard time getting started. Sagebrush provides habitat for the native mammals, birds, reptiles, and insects that evolved with it. These lovely native shrubs also change the way animals move across an area, how the wind moves, and how water moves.