The Ecology of Cheatgrass Invasion and Rangeland Repair C. Lynn Kinter Washington S.U.

Native in Eurasia Invasive in western North America Bromus tectorum L.

range (Mack 1981) founders (Novak & Mack 1993)

Plowed fields contaminant--wheat/alfalfa harvested with grain/straw/hay

Plowed fields contaminant--wheat/alfalfa harvested with grain/straw/hay Rangelands crust fragmentation livestockover-grazing rangeland fires

Plowed fields contaminant--wheat/alfalfa harvested with grain/straw/hay Rangelands crust fragmentation livestockover-grazing cheatgrass invasion rangeland fires

Plowed fields contaminant--wheat/alfalfa harvested with grain/straw/hay Rangelands crust fragmentation livestockover-grazing cheatgrass invasion rangeland fires increased fire frequency continued crust disturbance (Leopold 1941, Hironaka & Fosberg 1979, Mack 1981)

moves into openings disturbance gives cheatgrass an advantage (Moseley, Bunting, & Manoukian 1999)

germinates in fall roots develop through winter outcompetes native species for water in spring (Melgoza, Nowak, & Tausch 1990)

lbs of seed/acre (Stewart & Hull 1949)

invades many soil types: saline alkaline clay to sand gravel

Priorities for Rangeland Repair prevention is easier than control control of small isolated outbreaks (nascent foci) should have priority over control of the main invasion (Moody & Mack 1988)

Priorities for Rangeland Repair control should include establishing perennials (Mosley, Bunting, & Manoukian 1999) cheatgrass may be replaced by other invaders e.g. medusahead, yellow starthistle (Larson & Sheley 1994)

Where Native Plants are Abundant chemical control (Whitson & Koch 1998) apply > 1 year

Where Native Plants are Abundant chemical control (Whitson & Koch 1998) apply > 1 year grazing in winter when soils are firm and dry

Where Native Plants are Abundant chemical control (Whitson & Koch 1998) apply > 1 year grazing in winter when soils are firm and dry reducing fire frequency by: grazing (Vallentine & Stevens 1994, Mosley 1996) greenstrips (Pellant 1994)

Where Native Plants are Abundant—Don’t Use: prescribed fire

Where Native Plants are Abundant—Don’t Use: prescribed fire surface mechanical control (Pellant 1990)

Where Native Plants are Abundant—Don’t Use: prescribed fire surface mechanical control (Pellant 1990) fertilization (Wilson et al. 1996)

Where Native Plants are Scarce seeding of desired species, preceded by:

Where Native Plants are Scarce seeding of desired species, preceded by: prescribed fire in autumn, early grazing (Mosley, Bunting, & Manoukian 1999)

Where Native Plants are Scarce seeding of desired species, preceded by: prescribed fire in autumn, early grazing (Mosley, Bunting, & Manoukian 1999) chemical fallow or disking (Whitson & Koch 1998)

Choose NATIVES for reseeding!! Time (years) N lag phase “sleeper weeds” (Kowarik 1995)

Future Control Possibilities Squirreltail (Elymus elymoides = Sitanion hystrix) (Jones 1998; Booth, Caldwell, Stark 2003)

Head smut fungus (Ustillago bullata) (Meyer, Nelson, & Clement 2001)

Pseudomonas fluorescens D7 (Kennedy, Johnson, & Stubbs 2001)

Genetic manipulation???