Rare Idaho Plant To Be Listed As Threatened

Aug 16, 2016

A small, flowering plant that grows only in southwest Idaho is about to go back on the Endangered Species List. Slickspot Peppergrass has been there before, in 2009, but its status as “threatened” was challenged by Governor Butch Otter.

After years of legal wrangling, the U.S. Fish and Wildlife Service plans to put it back on the list next month.

Slickspot Peppergrass is a hairy green plant with white flowers, and is found in just a few areas of southwest Idaho.

Ian Robertson has a unique perspective on the plant. The Boise State biology professor has for nearly a decade been studying how Owyhee Harvester Ants affect Slickspot Peppergrass.

Owyhee Harvester Ants love the seeds of Slickspot Peppergrass.
Credit Ian Robertson / Boise State University

Robertson says the ants eat other things too, but to them, the peppergrass seeds are like chocolate is to humans. Seed predation is just one factor, along with wildfire, climate change and habitat loss, that’s affecting the plant.

“So all of these things combined make for a challenging life for these plants. If the habitat was much closer to its natural state, many of these concerns probably wouldn’t be there,” says Robertson.

Robertson is studying how Slickspot Peppergrass plants do when the Owyhee Harvester Ants are taken away. And he’s trying to plant seeds in new areas, to see if Slickspot Peppergrass can expand its range.

U.S. Fish and Wildlife plans to put the plant back on the “threatened” list on September 16.

Find Samantha Wright on Twitter @samwrightradio

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