Presentation on theme: "USE AND CONTROL OVER EXOTIC SPECIES IN RESTORATION"— Presentation transcript:
1 USE AND CONTROL OVER EXOTIC SPECIES IN RESTORATION Make sure this is in orderGroup 1Sara L. McPhersonErin SwallowNayeli Carvajal
2 Outline Terminology (Sara) Exotics in Mojave Desert: implication and prioritization (Sara)Approaches and Concerns in removing exotic (Erin)Removing exotic may threaten native species (Erin)Control Methods (Nayeli, Sara)Are there communities that are not invasible (Nayeli)Using exotic in restoration (Nayeli)Conclusion (Sara)
3 TerminologyExotic: any species that has established beyond their historical range (*Richardson, et al., 2000) accidentally or intentionally. Invasive: characterized by geographic distribution, the degree of threat whether socially, economically or environmentally (competitiveness, invasiveness, and ability to engineer ecosystems …Bromus and fire regimes) and control treatments.
4 Mojave Desert: Implications and Prioritization Research suggests invasions impose irreversible social, aesthetic, economic and environmental consequences.Exotic pose a serious threat in at least 194 of the 368 national park units in the USA (NPS, 1997).Management challenges arise because of the extreme variability of impactsConsider species in the Mojave ParksAbout 200 exotic species, prioritization is necessary because eradication of all exotics may not be a financially viable (billions annually)Early detection vs. eradication
5 Invasive Plant Species in Mojave Parks Figure 3Figure 1
6 Susceptibility & Resistance Disturbance regime, including type, frequency, duration and magnitude (Elton, 1958, Fox, 196, rejmakek, 1989).intermediate disturbance hypothesis (IDH) predicts the highest diversity may be strongest at intermediate (intensity, frequency, size, time)fuels reduction programs (Milberg, 1995; DAntonio, 2000b; 2000),post-wild-fire (planting for soil stabilization, silvi-culture and other forest management practices), spread/planting contaminated seedslivestock grazing (Hoobs, 1992), burrow and horses (hay)damaged soils/vegetation (*McDougall, et al., 2005),roadsides and railways (Wilson, 1992; Trombulak, 2000; Johnston, 2001; clear-cuts (Appleby, 1998)Mining (Lead, zinc, gold, silver, copper, gypsum, gravel, limestone)Northern and Eastern Mojave Desert Management Plan (NEMO), Desert Tortoise Recovery Plan, West Mojave Plan (WMP), The Federal Land Policy Management Act of 1976 (BLM purpose), California Desert Conservation Area (CDCA), Areas of Critical Environmental Concern (ACEC), Desert Wildlife Management Areas (DWMAs)
7 The diversity-invasibility paradigm There are two popular diversity-invisibility paradigmscompetitive exclusion (negative; small scale) and coexistence (positive; large scale; diverse communities are more prone to invasion);both assume resources are limiting, competition is a dominant structuring force in communities, and predict the similar natural patterns.Eltonian theory: low diversity habitats are more vulnerable to invasion than areas (ecosystems) of high diversity in other words increasing native diversity (richness) armors a community against invasion (repels invasion, decrease invasibility)..
8 Control Methods Mechanical: pulling, cutting or damaging the plant. Advantages: species specific and cost effectiveDisadvantage: labor and time intensive (Tue et. al.)Chemical: Use of herbicides which can be defined as any chemical substance that is used to specifically kill plants.Advantages: They are effective, work fast.Disadvantages: they may pose threats to the environment (non-biodegradable and slightly toxic). Some weeds may become resistant.Fig. 1:ativeLand/Chapter3/front%20covert.jpg
9 Biological control is the use of animals, fungi, or other microbes to feed upon, parasitize or otherwise interfere with a targeted pest species.Advantages: leaves no chemical residues.Disadvantages: some biological control programs have resulted in significant, irreversible harm to untargeted organisms and to ecological processesPrescribed burns: repeated burns are sometimes necessary to effectively control weedy plants.Fire is sometimes necessary to prompt the germination of some plants, including a number of rare and endangered species.Some natural areas such as DNWR does not use burns as a management tool due to their de facto wilderness management paradigm.Fig. 2: opics/sh ared_content/strawberryguava/images/galls.jpgTu, Mandy; Hurd, Callie and Randall, John Weed Control Methods Handbook: Tools and Techniques for Use in Natural Areas. The Nature Conservancy.Fig. 3: hreats/Prescribed_Fire_124.jpg
10 Prescribed grazing: Prescribed grazing is the application of domestic livestock grazing at a specified season and intensity to accomplish specific vegetation management goals. Typically employ domestic sheep, goats, and cattle; may also use horses, pigs, geese, or domesticated native ungulates (USFWS official website).Prescribed grazing systems incorporate aspects of both natural and domesticated grazing systems.Fig. 4: gMo dule/methods/grazing/introduction.html
11 A REVIEW OF CONTROL TREATMENTS FOR AMARANTHUS ALBUS (PIGWEED) Sara McPherson
12 Amaranthus albus (meaning everlasting white) Problematic Figure 5Figure 1 Distribution Map (USGS, 2006), Figure 2 Amaranthus albus (USGS, 2006). USDA, NRCS. Wetland flora: Field office illustrated guide to plant species. USDA Natural Resource Conservation. Service. Provided by NRCS National Wetland Team, Fort Worth, TX, Figure 3 Amaranthus albus (USGS, 2006). Robert H. Mohlenbrock. USDA, SCS, Midwest wetland flora: Field office illustrated guide. Midwest National Technical Center, Lincoln. Courtesy of USDA NRCS Wetland Science Institute.Scientific nameAmaranthus albus (meaning everlasting white)ProblematicVolume of seeds (30, ,000 per plant)(Acorn, 2001), virus AMV, crop landCommon namesprostrate pigweed, tumbleweed, tumbleweed amaranth, white amaranthCultural UseedibleFlowerJuly-AugustToxicityToxic to livestockBiologicalIn 1987, a fungus identified as Aposphaeria amaranthi usefulness as a control mechanismHerbicidesWeedScience.org (2002) reports herbicide resistanceHand laborbe hand weeded or hoed prior to the plants reaching seed production (Muenscher 1980)Mowing and Mechanicalsuggests that cultivation by surface tillage occur early to induce germination of seeds, followed by hand weeding or hoeing to prevent seed production by Amaranthus palmeri plants. Muenscher (1980)Figure 1 Distribution Map (USGS, 2006), Figure 2 Amaranthus albus (USGS, 2006). USDA, NRCS. Wetland flora: Field office illustrated guide to plant species. USDA Natural Resource Conservation. Service. Provided by NRCS National Wetland Team, Fort Worth, TX, Figure 3 Amaranthus albus (USGS, 2006). Robert H. Mohlenbrock. USDA, SCS, Midwest wetland flora: Field office illustrated guide. Midwest National Technical Center, Lincoln. Courtesy of USDA NRCS Wetland Science Institute.
13 StudyTreatmentResults Effectiveness of treatment(Ullia, et al., 2010)Propane flamingAbout 90% dry matter reduction achieved with propane dose ranging from 40 to 80 kg ha21(Amisi, et al., 2010)Raw dairy vs. composted manuresoils with raw dairy manure may decrease the competitiveness whereas composted manure increase competitiveness(Trader, et al., 2009)halosulfuron applicationsreduce shoot dry weight 50% compared with only 8 g/ha for S; differing degrees of resistance to halosulfuron.(Kahramanoglu, et al., 2010)metribuzinprovide satisfactory control (>90%) of redroot pigweed(Evans, et al., 2009)Clove oil and vinegar200-grain vinegar applied at 636 L/ha provided 100% control (6 d after treatment [DAT]) and mortality (9 DAT) of two-leaf redroot pigweed; as growth stage advanced, control and biomass reduction decreased and survival increased(Dahlquist, et al., 2007)TemperatureTemperatures of 50 C and above were lethal for seeds of all species. tumble pigweed unaffected at 42 C and below(Cristanudo, et al., 2007)At 10 and 15_C constant temperatures, no significant seed germination occurred there was no germination at 10_C, but at 15_C more than 60% germination occurred.(Treasdale, et al., 2005)Hairy vetch residue, ammonium hydroxideHairy vetch residue is capable of suppressing weeds, but low levels of residue can intermittently stimulate the emergence of weeds, particularly smooth pigweed. A similar response to ammonium hydroxide solutions was observed(Moran, et al., 2005)Water deficit and shade stressAll treatments decreased plant height and weight(Grichar, et al., 2005)atrazine, pendimethalin,trifluralinTumble pigweed was controlled at least 99% with atrazine plus pendimethalin or trifluralin application(Santos, et al., 2004)PhosphorusWeed-free lettuce fresh yield was 20% higher with banded P than broadcast applications.(Hanson, et al., 2003)fungicide propiconazolereduced the biomass accumulation 15 to 63%(Hendricks, et al., 1975)thiourea, sodium nitrite, hydroxylamine saltscatechol, pyrogallolGermination of some dormant seeds is promoted by solutions
14 References Put control references here Aguyoh Joseph N. and Masiunas John B. Inference of redroot pigweed (Amaranthus retroflexus) with snap beans [Journal] // Weed Science. - [s.l.] : Weed Science Society of America, : Vol pp DOI: / (2003)051[0202:IORPAR]2.0.CO;2, URL: Amisi Karen J. and Doohan Doug Redroot Pigweed (Amaranthus retroflexus) Seedling Emergence and Growth in Soils Amended with Composted Dairy Cattle Manure and Fresh Dairy Cattle Manure under Greenhouse Conditions [Journal] // Weed Technology. - [s.l.] : Weed Science Society of America, : Vol pp DOI: /WT , URL: Arianoutsou Margarita [et al.] The alien flora of Greece: taxonomy, life traits, and habitat preference [Journal] // Biol Invasions Vol pp DOI /s Cheplick Gregory P. Size and architectural traits as ontogenetic determinants of fitness in a phenotypically plastic annual weed (Amaranthus albus) [Journal] // Plant Species Biology Vol pp Cristanudo A. [et al.] Effects of after-harvest period and environmental factors on seed dormacy of Amaranthus species [Journal] // Journal Compliation. - [s.l.] : European Weed Research Society Research, Vol pp Dahlquist Ruth M., Prather Timothy S. and Stapleton James J. Time and Temperature Requirements for Weed Seed Thermal Death [Journal] // Weed Science . - [s.l.] : Weed Science Society of America, : Vol pp DOI: /WS , URL: Evans Glenn J., Bellinder Robin R. and Goffinet Martin C. Herbicidal Effects of Vinegar and clove oil product on redroot pigweed (Amaranthus retrjoflexus) and velvetleaf (Abutilon theophrasti) [Journal] // Weed Technology Vol pp DOI: /WT Grichar James W., Besler Brent A. and Brewer Kevin D. Weed Control and Grain Sorghum (sorghum biocolor) response to postermergence application of atrazine, pendimethalin, and trifluralin [Journal] // Weed Technology. - [s.l.] : Weed Science Society of America, : Vol pp DOI: /WT R2.1, URL: Habib S.A. and Rahman Addul A.A. Evaluation of some weed extracts against field doddger on alfalfa (Medicago sativa) [Journal] // Journal of Chemical Ecology : Vol. 14. Hanson Bradley D. [et al.] Growth Regulator Effects of Propiconazole on Redroot Pigweed (amaranthus retroflexus) [Journal] Vol pp Hendricks S.B. and Taylorson R.B. Breaking of Seed Dormacy by Catalase Inhibition [Journal] // Proc Nat Aca Sci. - January : Vol pp Jones Gretchen D., Greenberg Shoil M. and Eischen Frank A. Almond, Melon, and Pigweed Pollen Retention in the boll weevil (Coleoptera; Curculionidae) [Journal] // Palynology. - [s.l.] : AASP Foundation, pp Kahramanoglu Ibrahim and Uygur Nezihi F. The effects of reduced does and application timing of metribuzin on redroot pigweed (Amaranthus retroflex L.) and wild mustard (Sinapis arvensis L.) [Journal] // Turk J Argic For Vol pp doi: /tar Lovelli Stella [et al.] Photosynthetic Response to Water Stress of Pigweed (Amaranthus retroflexus) in a Southern-Mediterranean Area [Journal]. - [s.l.] : Weed Science Society of America, : Vol DOI: /WS , URL: Mirshekari Banram, Javanshir Aziz and Arbat Hamdollah Kazemi Inference of redroot pigweed (Amaranthus retroflexus) in green bean (Phaseolus vulgaris) [Journal] // Weed Biology and Management Vol pp Moran Patrick J. and Showler Allan T. Plant Responses to water deficit and shade stresses in pigweed and their influence on feeding and oviposition by the beet armyworm (Lepidoptera: noctuidae) [Journal] // Environ. Entomol : Vol pp Pribylova Radka [et al.] Detection of the antimicrobial peptide gene in different Amarathus species [Journal] // Biologia : Vol pp DOI: /s Santos Bielinski [et al.] Influence of method of phosphorus application on smooth pigweed (Amaranthus hybridus) and common purslane (Portulaca oleracea) interference in lettuce [Journal] // Weed Science Vol pp Sheibany Kabeh, Meubodi Mohammad Ali Baghestani and Atri Aliereza Competitive effects of redroot pigweed (Amaranthus retroflexus) on the growth indices and yield of corn [Journal] // Weed Biology Management Vol pp doi: /j x. Steinmaus Scott J., Prather Timothy and Holt Jodie S. [Journal] // Journal of Experimental Botany. - Febuary : Vol pp Trader Brian W. [et al.] Halosulfuron Resistance in Smooth Pigweed (Amaranthus hybridus) Populations [Journal] // Weed Techology. - [s.l.] : Weed Science Society of America, : Vol pp DOI: /WT , URL: Trader Brian W., Wilson Henry P. and Hines Thomas E. Control of Yellow Nutsedge (Cyperus esculentus) and Smooth Pigweed (Amaranthus hybridus) in Summer Squash with Halosulfuron [Journal] Vol pp DOI: /WT Treasdale John R. and Pillai Parthan Contribution of ammonium to stimulation of smooth pigweed (Amaranthus hybridus L.) germination by extracts of hairy vetch (Vicia villisa Roth) residue [Journal] // Weed Biology and Management Vol pp Trucco Federico [et al.] Characterization of Waterhemp (Amaranthus tuberculatus) × Smooth Pigweed (A. hybridus) F1 Hybrids [Journal] // Weed Technology. - [s.l.] : Weed Science Society of America, : Vol pp DOI: /WT R.1, URL: Ullia Santiago M., Datta Avishek and Knezevic Stevan Z. Growth Stage-Influenced Differential Response to Foxtail and Pigweed Species to Broadcast flaming [Journal] // Weed Technology Vol pp USGS [Online]. - Wassom J.J. and Tranel P.J. Amplified Fragment Length Polymorphism-Based Genetic Relationships Among Weedy Amaranthus Species [Journal] // Journal of Heredity : Vol pp doi: /jhered/esi065. Wicks Gail A. [et al.] Survey of Winter Wheat (Triticum aestivum) Stubble Fields Sprayed with Herbicides in 1998: Cultural Practices [Journal] // Weed Technology Vol ppPut control references here
16 In which instances have exotic plants been used for restoration? Prevent soil erosion: where soil erosion or the potential for it is severe practitioners use fast-growing but sterile exotic grasses to quickly establish cover (D’Antonio and Meyerson, 2002).Figure 6:http://www.forestandrange.org/rangeland%20weeds%20 module/img/sub3-4_SpottedKnapweedPresc.jpgEnrich sterile soils: In other cases where land uses such as mining and overgrazing have reduced soil fertility, fast-growing exotic species (N-fixing) have been used to ameliorate harsh conditions may eventually accelerate the recover of natives (D’Antonio and Meyerson, 2002) (Nevada Test Site).In some degraded sites it may be necessary to introduced an exotic species to assist in the restoration process (D’Antonio and Meyerson, 2002).Nitrogen-fixing species - Nitrogen-fixing species are generally essential for adding nitrogen and building soils on landslides or other disturbed areas that have shallow or undeveloped soils. Most nitrogen-fixing species require innoculation and may benefit from phosphorous fertilization. Innoculation involves the introduction of the specific nitrogen-fixing bacteria to the roots or seed of the plant before planting. One common practice is to collect and use the soil duff or litter adjacent to the same species growing in the field to inoculate the roots or seed before planting.Figure 7:
17 Secure the site: Alien species that form dense colonies can help reduce invasions by other aliens (Ewel and Putz, 2004).Nurse Plants: By shielding against intense radiation and heat loading, the light shade east by some plants can facilitate colonization by others (Ewel and Putz, 2004).Guide composition: Selective consumption of an alien plant by an alien herbivore can direct succession towards vegetation of a desired life form (Ewel and Putz, 2004).Provision of surrogate resources: True restoration of the original ecosystem is sometimes impossible due to extinctions, but can be approximated by using non-native species (Ewel and Putz, 2004).
18 Biological control: Use of exotic species that predate on or compete with the invasive species (D’Antonio and Meyerson, 2002).Release of insect as a control method for controlling exotic plants (Pearson et al., 2000)Fig 8. Spotted knapweed (Centaurea maculosa)Fig 9. Gall fly (Urophora quadrifasciata)
19 Why we shouldn’t use exotic plants for restoration? In some cases exotic grasses may reduce the growth of native seedling in the critical first years after disturbance (D’Antonio and Meyerson, 2002).Unplanned biological control may result in introduced species becoming invasive themselves.
20 RecommendationsThe exotic species used for restoration should themselves not be invasive or have the potential to become problematic (D’Antonio and Meyerson, 2002).Consider the options carefully. The effects of the introduction of these biological controls have not been studied in depth (D’Antonio and Meyerson, 2002).Depends on the goal of the restoration project. If the goal of the project is full recovery of native assemblage then exotic plants should not be used for restoration(D’Antonio and Meyerson, 2002).ConsiderCostBenefitRisk
21 ReferencesD’Antonio, Carla and Meyerson, Laura Exotic Plant Species as Problems and Solutions in Ecological Restoration: A Synthesis. Restoration Ecology. Vol. 10:Ewel, John and Putz, Francis. A place for alien species in ecosystem restoration. Frontiers in Ecology and the Environment Vol.2:Dean E. Pearson, Kevin S. McKelvey, Leonard F Non-Target Effects of an Introduced Biological Control Agent on Deer Mouse Ecology. Oecologia, Vol. 122, No. 1 (2000), ppRuggierohttp://www.forestandrange.org/rangeland%20weed.s%20m odule/img/sub3-4_SpottedKnapweedPresc.jpg3/p4.shtml
22 Things TO CONSIDER IN Invasive Species Management and Control Erin Swallow
23 Overview Introduction Practical: Bromus rubens Political: Wild horses Why do we need to remove it anyway?TamarixPhragmites spp.Impacts of Removal: Tanta natansUnexpected Consequences: Santa Cruz Islands
24 IntroductionIt is not as simple as deciding to remove a species not native to an areaA variety of issues must be consideredFeasibilityCostConsequences – to the environment, other species and the community
25 Practical Successful control requires adequate Money - $32 - $42 million spent annually on plant and animal management under ESA – 90% related to exoticsTime – Hand removal is time and labor intensiveOngoing support – Common reed removal takes years of follow-upIn some cases, the species is to well established to be completely removed
26 Bromus rubens Red brome Invasive Mediterranean grass Increases fire hazardThoroughly naturalizedBest option to limit spread, not eradicateFigure 10:
27 Political Control of exotics can be controversial Figure 11Control of exotics can be controversialCulling species – Animal rightsUninformed public – tree clearing, burnsCost
28 Wild Horses and BurrosProtected by the Wild and Free-roaming Horses and Burros Act (1971)BLM mandated to control populationsNot given adequate resourcesFigure 12
29 Wild Horses and Burros Overpopulating the range Realistic management unacceptable to the publicIssues of competition and disturbance persistFigure 13
30 Impacts of RemovalThe act of removal can negatively impact the overall environmentDisturbance from removalLingering impacts from chemicals
31 Trapa natans European water chestnut Invasive water plant that forms thick mats in waterwaysInterferes with light penetration, fish communities, dissolved oxygen, recreationFigure 14
32 Trapa natans Small infestations can be removed by hand Figure 15Small infestations can be removed by handLarge infestations require repeated dredgingMount HolyokeDredgedDrainedRemoved sedimentFigure 16(both from same page)
33 Why do we need to remove it anyway? Not all exotic species are causing significant harm…some may even help certain species!
34 Phragmites spp. What is it? Concerns: Common reed Aggressively colonizes wetlandsConcerns:Reduced biodiversityLost ecosystem servicesFigure 17
35 Phragmites spp. Early colonizer – stabilizes soil, provides habitat Cover for wildlifeNestingForagingProtection from predatorsProtection from elementsExpensive and difficult to removeRecolonizes quicklyFigure 18
36 Unexpected Consequences Ecological systems are interconnected, any change can have unforeseen consequencesNeed to consider carefully before action is taken
37 Tamarix What is it? Concerns: Saltcedar, Tamarisk Colonizes along water waysConcerns:Water supplyWildlife habitatChanges soil propertiesSpecies diversityFigure 19
38 Tamarix Erosion control Birds Southwestern Willow FlycatcherYellow-billed cuckooLeveling Tamarix without adequate follow-up destroys bird habitatFigure 20
39 Santa Cruz Island Overgrazed by feral pigs and sheep Threatened the endangered Santa Cruz Island fox and other speciesDDT wiped out bald eaglesGolden eagles arrived – preyed on pigs and foxesRestoration efforts removed pigs and sheep
40 Santa Cruz IslandPig removal lead to increased predation pressure on foxesEndangered golden eagles removed and bald eagles reintroducedFigure 21
41 ReferencesBenoit, L. K., and R. A. Askins Impact of the spread of Phragmites on the distribution of birds in Connecticut tidal marshes. Wetlands 19: California: Santa Cruz Island Nature Conservancy. lifornia/preserves/art6335.html Chambers, R. M., L. A. Meyerson, and K. Saltonstall Expansion of Phragmites australis into tidal wetlands of North America. Aquatic Botany 64: D’Antonio, C., and L.A. Meyerson Exotic plant species as problems and solutions in ecological restoration: a synthesis. Restoration Ecology 10: De Corte, A Relationshisp of exotic plant invasions with biological soil crust, desert pavement and soil carbon in the eastern Mojave desert. Master’s thesis, University of Nevada, Las Vegas Farnsworth, E., and L. Meyerson Species composition and inter-annual dynamics of a freshwater tidal plant community following removal of the invasive grass, Phragmites australis. Biological Invasions 1: Faulds, A., and K. Wakefield Phragmites: a tale of two strains. Pennsylvania Sea Grant. ybryant.com/marsh/phragDocs/PhragmitesATaleOfTwoStrains.doc. Meyer, S. W Comparative use of Phragmites australis and other habitats by birds, amphibians, and mammals, at Long Point, Ontario. Master’s thesis, University of Western Ontario. Meyerson, L. A., K. Saltonstall, L. Windham, E. Kiviat, and S. Findlay A comparison of Phragmites australis in freshwater and brackish marsh environments in North America. Wetland Ecology and Management 8: North, S Damage control: MHC and the attempt to control the waterfront environment. Mount Holyoke Historical Atlas. /hat las/water relationship/modern/dredging.html O’Neill, C. R Water chestnut (Trapa natans) in the northeast. NYSG Invasive Species Fact Sheet Series: New York Sea Grant 1-4. Pitt, K. P Wild free-roaming horses and burros act: a western melodrama. Environmental Law 15: Sogge, M. K., S. J. Sferra and E. J. Paxton. Tamarix as habitat for birds: implications for restoration in the southwestern United States. Restoration Ecology 16:
42 Conclusion Where do we go from here? Prevention (early detection; critical) vs. eradicationFoundation for prevention, eradication and control (Abella, Spencer, Hoines, & Nazarchyk, 2009; Hobbs & Humphries, August 1995; Hulme, 2006)9factors hunger management:scientific research has a current symposium encompasses 120 competing hypothesesthe quantity of highly invasive candidate (tens of thousands; Sax & Brown, 2000),ability to discern significant changes,inadequate tracking indicators,predictability of regional composition and introduction models,lag times in population explosion,timing of control measuresystems for assessing harmful species not presently documented in the region and corresponding adaptive monitoring for potential invaders (Hulme, 2006).
44 LiteratureAbella SR [et al.] Relationship of native desert plants with red brome (Bromus rubens): twoard indentifying invasion-reducing species [Journal] Bakker JD and Wilson SD Using ecological restoration to constrain biological invasion [Journal] // Journal of Applied Ecology Vol pp Brown CS [et al.] Restoration ecology and invasive plants in the semiarid West [Journal] // Invasive Plant Science and Management Vol pp D'Antonio C. and Meyerson L.A. Exotic plant species as problems and solutions in ecological restoration: a synthesis [Journal] // Ecology Letters Vol pp Lodge DM [et al.] Biological invasions: recommendations for US policy and management [Journal] // Ecological Applications Vol pp Prober SM [et al.] Restoring ecological function in temperate grass woodland: manipulating soul nutrients, exotic annuals and native perennial grasses through carbon supplements and spring burns [Journal] // Journal of Applied Ecology Vol pp Sandel B. and Corbin JD Scale, disturbance and productivity control the native and exotic richness relationship [Journal] // Oikos Vol pp SEARCH. - doi: /j x. Zouhar K. [et al.] Wildliand fire in ecosystems: fire and nonnative invasive plants [Journal]. - [s.l.] : General Technical Report RMRS-GTR-42-vol 6 US Department of Agriculture Forest Service Rocky Mountain Research Station, p. 355 pp.