In February and March 2008, volunteers assisted Grand Canyon National Park’s Science and Resource Management staff in removing the aggressive invasive plant commonly known as Sahara mustard (Brassica tournefortii) at Lees Ferry. Sahara mustard, a new arrival to the area, poses a serious ecological threat to the Grand Canyon ecosystem. In the past few years, Sahara mustard has become one of the most dominant plants found near the mouth of the Paria River and it now literally surrounds the campground at Lees Ferry.
Sahara mustard is native to north Africa, southern Europe, and the Middle East. It is adapted to arid climates and sandy soils. Although it was first recorded in California in the 1920s, it has spread in the last few years throughout the low elevations of the deserts in California and Arizona, and east to New Mexico and Texas. Sahara mustard now forms a dense blanket in some portions of Glen Canyon National Recreation Area, and is threatening the survival of rare dune plants at Lake Mead National Recreation Area. Some ecologists in California worry that entire ecosystems may be at risk because of Sahara mustard; other scientists have warned that native vegetation in entire national parks could be destroyed in decades.