California Invasive Plant Council

Bromus tectorum

Common names: cheatgrass; downy brome

Bromus tectorum (downy brome, cheatgrass) is an annual grass (family Poaceae). It is the dominant grass on sagebrush (Artemisia species) rangelands on the Modoc Plateau in northeastern California and along the eastern Sierra Nevada to Owens Valley. This weed overcrowds native grasslands and croplands. Replacement of native grasses by cheatgrass increases the frequency and extent of wildfires.

Cal-IPC Rating: High?

Explanation of Cal-IPC ratings

• High – These species have severe ecological impacts on physical processes, plant and animal communities, and vegetation structure. Their reproductive biology and other attributes are conducive to moderate to high rates of dispersal and establishment. Most are widely distributed ecologically.
• Moderate – These species have substantial and apparent-but generally not severe-ecological impacts on physical processes, plant and animal communities, and vegetation structure. Their reproductive biology and other attributes are conducive to moderate to high rates of dispersal, though establishment is generally dependent upon ecological disturbance. Ecological amplitude and distribution may range from limited to widespread.
• Limited – These species are invasive but their ecological impacts are minor on a statewide level or there was not enough information to justify a higher score. Their reproductive biology and other attributes result in low to moderate rates of invasiveness. Ecological amplitude and distribution are generally limited, but these species may be locally persistent and problematic.
• Alert – An Alert is listed on species with High or Moderate impacts that have limited distribution in California, but may have the potential to spread much further.
• Watch – These species have been assessed as posing a high risk of becoming invasive in the future in California.

CDFA Rating: C?

Explanation of CDFA ratings

• A – A pest of known economic or environmental detriment and is either not known to be established in California or it is present in a limited distribution that allows for the possibility of eradication or successful containment.
• B – A pest of known economic or environmental detriment and, if present in California, it is of limited distribution.
• C – A pest of known economic or environmental detriment and, if present in California, it is usually widespread.
• D – An organism known to be of little or no economic or environmental detriment, to have an extremely low likelihood of weediness, or is known to be a parasite or predator.
• Q – An organism or disorder suspected to be of economic or environmental detriment, but whose status is uncertain because of incomplete identification or inadequate information.
• * – An asterisk next to the rating indicates that a plant is included in the CCR Section 4500 list of California State Noxious Weeds.
• -* – This plant is included in the CCR Section 4500 list of California State Noxious Weeds, but is otherwise not rated.

More details

Assessment(s)

Bromus tectorum Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.

Species ID Card

Invasive Species ID Card - To support field identification of early detection species, Cal-IPC has designed a set of Species ID cards that can be downloaded, printed double-sided, and trimmed to size.

Weed Management Notes

• Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.

Cal-IPC Newsletter Articles

• One Tam unites around Marin’s mountain. Kesel, Rachel. Vol 24, Issue 3
• Native soil bacteria as biocontrol. Bean, Travis; Gornish, Elise. Vol 24, Issue 2
• Cheatgrass in erosion control projects. Etra, Julie; Juncosa, Adrian. Vol 20, Issue 1
• Wildland Weed News. Cal-IPC. Vol 20, Issue 1
• Wildland Weed News. editor. Vol 17, Issue 2
• Biological control of invasive exotic pest plant species: A report on the importance of maintaining and enhancing our nation’s biological control capabilities. CalEPPC. Vol 03, Issue 3
• Exotic pest plants of greatest ecological concern in California September 1994. Cal-IPC. Vol 02, Issue 4
• California Exotic Pest Plant Council draft list exotic plants of greatest concern October 1993. CalEPPC. Vol 01, Issue 4

Cal-IPC Symposium Presentations

Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.

• Biogeographical patterns of the rhizosphere microbiome of a native and invasive grass in the western United States. Mueller, Rebecca (2023)
• Biological control of invasive annual grasses. Rector, Brian (2023)
• Cheatgrass in the sagebrush: Implications of habitat loss and conversion on sagebrush-dependent species, using the Greater Sage-Grouse and Mule Deer as indicator species. Andrle, Katie (2023)
• Effective cheatgrass control with fluazifop-p-butyl in the coast range, Marin County. Greenberger, David (2023)
• Managing invasive annual grasses through the Sage Grouse Initiative. Heater, Thad (2023)
• Update on recent biological control releases against invasive plants by the USDA-ARS. Moran, Patrick; Pratt, Paul; Smith, Lincoln (2022)
• Using selective herbicides to control invasive annual grasses. Echols, Aaron (2022)
• Weeds and seeds and fire, oh my! Weed management lessons from Montana. Mangold, Jane (2022)
• Winter annual grass control: experiences with Indaziflam in NE California. Getts, Tom (2022)
• Effectiveness of pre-emergent herbicides in rangeland rehabilitation. Clements, Charlie; Harmon, Dan (2020)
• Interactions among insects and weeds in western U.S. forests. Fettig, Christopher; Runyon, Justin; Trilling, Jared; Mortenson, Leif; Audley, Jackson (2020)
• Perturbations in fire-prone ecosystems resulting in exotic plant invasions. Keeley, Jon (2020)
• Mapping weeds and rare plants to inform management and conservation in the Zaca and Jesusita fires. Calloway, Stephanie; Schneider, Heather; Knapp, Denise (2018)

Other Bromus tectorum Information

• Bugwood - National database from the Center for Invasive Species and Ecosystem Health at the University of Georgia.
• CalPhotos - Images of plants taken mostly in California.
• Calflora - Distribution map and records of this species in California.
• CalWeedMapper - Distribution map of this species in California with ability to determine regional priorities.
• EDDMapS - Distribution of this species in North America.
• Jepson Interchange - Information on this plant's taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
• USDA PLANTS Database - Information on identification and distribution, with links to websites in individual states.

Additional photos