Beware of the Ravenous Ravenna Grass: Early Detection and Treatment of the Invasive Exotic Ravenna Grass (Saccharum Ravennae) in the Colorado River Watershed
Curtis Deuser1*, Melissa McMaster2, Lori Makarick3, John Spence4
1Lake Mead Inter-Regional Invasive Plant Management Team 601 Nevada Highway, Boulder City, NV 89005; Curt_Deuser@nps.gov
2114 N. San Francisco St. Suite 3, Flagstaff, AZ 86001; Melissa@mariposaeco.com
3National Park Service, 1201 Oakridge Dr. Suite 200, Fort Collins, CO. 80525; Lori_Makarick@nps.gov
4Glen Canyon National Recreation Area, 691 Scenic View Dr. PO Box 1507, Page, AZ 86040; John_Spence@nps.gov
Ravenna grass (Saccharum ravennae) is a large ornamental bunchgrass that was introduced from Eurasia and threatens riparian areas in the desert southwest. Although not widely distributed yet this plant is highly invasive and competitive, it produces large quantities of seeds that are wind and water dispersed and germinate quickly and easily in a variety of soil and canopy conditions. It is important to aggressively treat Ravenna grass with high priority due to its potential to expand after suppression of tamarix species from biological control. Currently, most populations are scattered and relatively small and categorized in the early detection rapid response weed control strategy. Ravenna grass is of special concern to land managers as it has the ability to displace and out-compete important native and endemic plants species and create dense patches that become impenetrable and result in monocultures. Control methods can involve digging up the root mass or applying herbicide to the foliage. Ravenna grass control efforts by the National Park Service at Glen Canyon National Recreation Area, Grand Canyon National Park and in the Moapa Valley National Wildlife Refuge in Southern Nevada have greatly reduced population levels. Ravenna grass plant identification, awareness and education are essential to prevent this weed from expanding and becoming a widespread problem.