Red Brome www.forestryimages.org/.../3072x2048/5391954.jpg Anita Thompson NRES 441 Invasive Plants http://www.californiachaparral.com/adesertfires.html Scientific and common names Family – Poaceae (Grasses) Names can be confusing and/or location dependent! • Foxtail chess – Bromus madritensis L. • Red brome – Bromus rubens L. Or by subspecies • Foxtail chess – Bromus madritensis ssp. madritensis • Red brome is a subspecies of foxtail chess – Bromus madritensis ssp. rubens (L.) Or by location • Foxtail chess (for the species as a whole) – Bromus madritensis • Red brome (for most of the United States) – Bromus madritensis ssp. rubens •Red Brome (for California/where some foxtail chess and red brome populations overlap) – Bromus rubens Scientific and common names Synonyms: • Anisantha madritensis (British Isles) Common names: • Foxtail chess • Compact brome • Spanish brome • Red Brome http://www.birdandhike.com/Veg/Species/Grass/Bromus_rub/_Bro_rub.htm Invasive classification: Not listed federally at this time Not listed in Nevada at this time Listed in California • CA Invasive Plant Inventory • CA Exotic Pest Plant Council Foxtail chess on the A-1 list: most invasive wildland plants; widespread. extension.usu.edu/range/Grasses/redbrome.htm Plant Description • Cool season, annual grass • Culms (stems) are several to numerous - 4 to 28 inches tall • Spike-like Panicle inflorescence, 1 to 4 inches tall with long awns (1/2 to 1 inch long). Seedhead is reddish-purple when mature. • Blades are short, narrow and flat with prominent veins. Ligule: 1/8 in. long • In comparison to foxtail chess which has hairier stems and leaf sheaths, more lax panicles and wider lemmas. www.plantzafrica.com/plantefg/grassdraw.htm Foxtail chess http://www.researchlearningcenter.com/bloom/queries_s pecial/Grasses.htm www.arizonensis.org/.../bromus_rubens.html Red brome Site Characteristics Nevada: • Blackbrush (Coleogyne ramosissima) communities. • Creosote/blackbrush transition zones • Creosote/saltbrush/blackbrush communites In Utah and Arizona: • Sagebrush communties • Desert scrub • understory of mature mesquite bosques Foxtail chess is an invader of the historical perennial grasslands of California. Prefers disturbed sites Prefers Mediterranean sites (dry summers, wet winters) but can occur in drier climates. Site characteristics cont. Elevations: • CA: up to 7200’ • NV: 1200 to 5000’ • UT: 2500 to 5500’ • AZ: Sea level to 4100’ Precipitation: • site dependent • 2” to 10” • In the Mojave, preferred 2-4” annual precipitation Soils: • Shallow, coarse textured • Little competition from other annuals • Likes shrub canopies • Some areas – clay and sandy loams • Can be found in areas with high levels of sulfur dioxide pollution. (Acid rain/sulfur emissions) Geographic Range Origins: • Red brome – Native throughout southern Europe • Foxtail chess – Native throughout Europe and British Isles Currently found in: • WA south to CA, east to ID, TX and Sonora (Mexico) • Casually adventive (not native and not fully established) in the Northeast (NY, MA, MY, VA, SC) and introduced in HI Introductions Three main ideas: • California Gold Rush/Central Valley Wheat • Southern California shipping • Northern California sheep Accidental Introduction from Mediterranean • Occasional intentional plantings (grazing/cultivation?) Introduced prior to the1880’s • Earliest herbarium record – 1879 in Plumas County, CA. Invasiveness Red brome is an annual winter grass • Germination is a direct response to fall rains • Slow growth until spring rains • Rapid increase in vegetation growth after spring rains • Flowering/fruiting occur in April and May • Seed dispersal in summer Prolific seed producer – averages 76 seeds/plant Prefers disturbed areas Requires less moisture than natives Rarely grazed (little nutritional value, ripe seedheads/awns dangerous to livestock) Very responsive to over-grazed and post-fire areas Problem #1 – Grazing disturbance Overgrazing/range overuse issue Opens up spaces (gaps) between other native grasses and shrubs for successful germination • Red brome is shade intolerant • “Hoof action” stirs up soils • Seed can be from on or off site sources Carried from one site to another by hoof, fur, etc • Red brome germination traits enable it to germinate and grow faster than annuals. • Not just a domestic grazer issue • Plant is not a preferred browse Sheep will graze in winter www.rci-nv.com/photos/rangeland1.jpg http://www.nature.org/wherewework/northamerica/states/oklahoma/about/rangeland.html Problem #2 - Fire Number 1 management issue! • Shortens fire return intervals by increasing potential starts and rate of spread. • Promotes fire where fire was previously infrequent (ex. Desert environments) • Produces a large amount of fine fuels that may lead to fast and hot fires (light and “flashy fuels”). • May be more of an issue than cheatgrass Natural ranges usually have lower humidity – leads to slower biomass breakdown. This leads to fuels persisting for longer periods Why is Red Brome a Fire Management Issue? Pre-fire: Red brome grows in areas that were once either open gaps (vacant niches) or filled with native annuals that were out competed. Red brome interspersed with native plants http://www.birdandhike.com/Veg/Species/Grass/Bromus_rub/_Bro_rub.htm Post-fire: Fire return interval is now shortened = more frequent fires Native shrubs are killed = loss of habitat, food value and recreational/aesth etic values Red brome now has more spaces to germinate Other fire management considerations: • Occurs mainly in non-fire adapted ecosystems • Low intensity winter fires are not high enough to kill seeds (but can kill vegetation). • Can initially be an off site colonizer and then move to the disturbed sites • Does not have a large (if any) seed bank •Fires can affect endangered wildlife Ex. Federally threatened desert tortoise (Gopherus agassizii) Mojave desert dweller Fires have reduced food sources (native grasses, cacti) and habitat (shrubs required for shading and protection from predators Ecological and Societal Impacts Ecological: • Threatened and Endangered Species (i.e. Tortoise) • Loss of habitat and food sources for non T&E species • Increased frequency of fires • Potential soil/nutrient losses • Succession issues (succession can stay in early seral stages) Societal Impacts: • Lowered recreational/aesthetic value • More fires = more suppression efforts = more $ • Wildland – Urban Interface issues (loss of homes, etc) • Loss of functional grazing lands = higher cost to livestock producers = higher cost to consumers • High costs for containing/managing R. brome Management Strategies The Nature Conservancy Stewardship Abstract recommends: • Management: Reducing seed heads Re-seeding with native annuals • Mechanical control: Removal of seedlings by hoeing or hand removal Time consuming but reduces future seeds Mulching with 5 to 13 cm of mulch or a layer of black plastic. (Site specific) • Burning and Grazing: Late-fall burns can damage R. Brome seed heads and encourage perennial grasses. Some grazing by sheep in winter can increase native bunchgrass Management Strategies cont. •Herbicides: Most effective control would be pre-emergent herbicides (kill seeds before germination) But would also kill native annual seeds Recommends atrazine – 11.2 kg atrazine per hectare Disadvantage: toxic effects lasted in surrounding vegetation for 8 years •Continued monitoring and research Case study: Anaho Island •Original survey (thesis) in 1966 by W.V. Woodbury. •Research published in 1991 (see works cited) by T. Svejcar and R. Tausch. •Surveyed for USFWS in 2009 by S. Kulpa, et al. (unpublished data) plpt.nsn.us/geology/images/fig26.jpg • Largest island in Pyramid Lake, NV • 750 acres in size • highest point is 540 ft above lake level (over 4300 ft above sea level) • National Wildlife Refuge • No record of intentional grazing or burning • Inhabited by nesting birds (and rattlesnakes) • Possible remains of sheep and goats (1966) http://www.sangres.com/nevada/wildlife-refuges/anaho-island.htm Anaho Island cont. 1966, B. rubens was common (2150%) only in the upper terraces, but occurred occasionally (6-20%) the shoreline and lower terraces of the NE side Kulpa, S. Unpublished data 2009, B. rubens was very common (50%+) to common on most of the island. It was not surveyed on the lower NE terraces due to pelican nests. Anaho Island cont. What they learned/observed: • The lower elevations were more dominated by perennial natives • The higher elevations had higher exotic annuals •Possibly due to higher thatch levels from lack of herbivores. Unknown as to why or how Red brome is the dominant annual on the island. • Different plant genotypes? • Nesting birds providing nutrient inputs? • Lack of herbivory? • Is the island environment a factor (isolation)? Other interesting facts: S. Kulpa • Red brome outcompeted cheatgrass (Bromus tectorum) in many places. • Fire establishment on the island would be catastrophic • Island is over run with rattlesnakes. How did they get there? Did they kill off the herbivores who feed on the grass seeds? THE END!!! Works cited Bowers, Michael A. 1987. Precipitation and the relative abundances of desert winter annuals: a 6-year study in the northern Mohave Desert. Journal of Arid Environments. 12: 141-149.  Kulpa, S., 2009. Anaho Island Research (unpublished data). Reid, C.R., S. Goodrich and J.E. Bowns. 2008. Cheatgrass and Red Brome: History and Biology of Two Invaders. Proceedings - Shrublands under fire: disturbance and recovery in a changing world. Proc. RMRS-P-52. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. Salo, L.F. 2004. Population dynamics of red brome (Bromus madritensis subsp. Rubens): times for concern, opportunities for management. Journal of Arid Environments 57: 291-296. Salo, L.F. 2005. Red brome (Bromus rubens subsp. Madritensis) in North America: possible modes for early introductions, subsequent spread. Biological Invasions 7: 165-180. Simonin, Kevin A. 2001. Bromus rubens, Bromus madritensis. In: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/ [ 2010, April 30]. Svejcar, T. and R. Tausch. 1991. Anaho Island, Nevada: A Relict Area Dominated By Annual Invader Species. Rangelands 13(5): 233-236. The Nature Conservancy. 2001. Element Stewardship Abstract For Bromus rubens. http://www.imapinvasives.org/GIST/ESA/esapages/documnts/bromrub.pdf, [2010, April 30]. Utah State University Extension. 2002. Red Brome. http://extension.usu.edu/range/Grasses/redbrome.htm, [2010, April 30].