University of Denver

Anna Sher has spent more than a decade trying to protect Colorado’s ecosystem.Sher, an associate professor of biology, has been researching effective ways to prevent the spread of tamarisk, an invasive species of weed that can drive off native wildlife. She's traveled the West, studied the ecological impacts and potential solutions and lobbied for change and involvement."The problem with tamarisk is that it's able to establish itself and effect other changes to the ecosystem that are harmful to the original plants and animals," says Sher, who also directs research, herbaria and records at the Denver Botanic Gardens. "It changes the structure of the forest."

Imported from Asia in the 1800s as an ornamental, tamarisk spread from gardens to natural waterways, boosted along the way by planting programs to control erosion. It spread across the West, and concentrations are now found on an estimated two million acres throughout the Western and Southwestern U.S.The plant, also known as salt cedar, creates salty soil conditions around it -- conditions that are inhospitable to native plants. It can also increase fire intensity and frequency. And tamarisk gobbles up water, depriving farmers and cities downstream.