Seminal paper showing that Phragmites expansion in North America caused by non-native genotypes

Saltonstall, K. (2002), Cryptic invasion by a non-native genotype of the common reed, Phragmites australis, into North America. Proceedings of the National Academy of Sciences, 99(4): 2445-2449

Modes of reproduction

Rhizomes of non-native Phragmites can break off and establish new populations

• Bart, D., & Hartman, J.M. (2003), The role of large rhizome dispersal and low salinity windows in the establishment of common reed, Phragmites australis, in salt marshes: new links to human activities. Estuaries, 26(2):436-443.

The frequency of sexual reproduction is greater for non-native than native Phragmites

• Kettenring, K.M., & Mock, K.E. (2012), Genetic diversity, reproductive mode, and dispersal differ between the cryptic invader, Phragmites australis, and its native conspecific. Biological Invasions, 14(12): 2489–2504.

Seed as dominant driver of spread

Seed studies and measures of genetic diversity demonstrate that sexual reproduction via seed is dominant factor in invasion of Phragmites across landscape

• Kettenring, K.M., & Whigham, D.F. 2009, Seed viability and seed dormancy of Phragmites australis in suburbanized and forested watersheds of the Chesapeake Bay, USA. Aquatic Botany, 91(3):199-204.
• McCormick, M.K., Kettenring, K.M., Baron, H.M., & Whigham, D.F. (2010), Spread of invasive Phragmites australis in estuaries with differing degrees of development: genetic patterns, Allee effects and interpretation. Journal of Ecology, 98:1369-1378.
• McCormick, M.K., Kettenring, K.M., Baron, H.M., & Whigham, D.F.. (2010), Extent and reproductive mechanisms of Phragmites australis spread in brackish wetlands in Chesapeake Bay, Maryland (USA). Wetlands, 30(1): 67-74.
• Albert, A., Brisson, J., Belzile, F., Turgeon, J. & Lavoie, C. (2015) Strategies for a successful plant invasion: the reproduction of Phragmites australis in north-eastern North America. Journal of Ecology, 103, 1529–1537.
• Fant, J.B., A.L. Price, and D.J. Larkin. 2016. The influence of habitat disturbance on genetic structure and reproductive strategies within stands of native and non‐native Phragmites australis (common reed). Diversity and Distributions 22:1301-1313.

Shoreline hardening promotes establishment of multiple Phragmites genotypes, thus further increasing the potential for increased viable seed production.

• McCormick, M.K., Whigham, D.F., Stapp, J.R., Hazelton, E.L.G., McFarland, E.K., Kettenring, K.M. (2020), Shoreline modification affects recruitment of invasive Phragmites australis. Wetlands Ecology and Management, 28(6):909-919.

Importance of genetic diversity in seed production

Larger non-native Phragmites patches have more genetic diversity, which increases the chances for cross-fertilization which can increase local levels of genetic diversity, which can further facilitate the spread of non-native Phragmites by seed

• Kettenring, K.M., McCormick, M.K., Baron, H.M. et al. (2010), Phragmites australis (common reed) invasion in the Rhode River subestuary of the Chesapeake Bay: disentangling the effects of foliar nutrients, genetic diversity, patch size, and seed viability. Estuaries and Coasts, 33(1): 118-126.

Seed viability of non-native Phragmites was positively related to patch-level genetic diversity and patches in more developed watersheds had higher genetic diversity. Non-native Phragmites plants in larger patches produced a higher proportion of viable seeds. Elevated nutrients resulted in greater floret and inflorescence production

• Kettenring, K.M., McCormick, M.K., Baron, H.M., & Whigham, D.F. (2011), Mechanisms of Phragmites australis invasion: feedbacks among genetic diversity, nutrients, and sexual reproduction. Journal of Applied Ecology, 48:1305-1313.

Stands of non-native Phragmites being closer to other non-native Phragmites patches facilitates spread

• Kirk, H., Paul, J., Straka, J., & Freeland, J.R. (2011), Long‐distance dispersal and high genetic diversity are implicated in the invasive spread of the common reed, Phragmites australis (Poaceae), in northeastern North America. American Journal of Botany, 98: 1180-1190.

Rates of spread

8% annual increase in non-native Phragmites percent cover in New England salt marshes

• Burdick, D.M., Buchsbaum, R., & Holt, E. (2001), Variation in soil salinity associated with expansion of Phragmites australis in salt marshes. Environmental and Experimental Botany, 46(3): 247-261.

11-46% annual increase in percent cover of non-native Phragmites

• Kettenring, K.M., Mock, K.E., Zaman, B., & McKee. M. (2016), PhragNet: crowdsourcing to investigate ecology and management of invasive Phragmites australis (common reed) in North America. Biological Invasions, 18(9): 2475-2495.

Recently established non-native Phragmites patches had much higher annual intrinsic rates of increase than older patches

• Rice, D., Rooth, J., & Stevenson, J.C. (2000), colonization and expansion of Phragmites australis in upper Chesapeake Bay tidal marshes. Wetlands, 20(2): 280-299.

Estimate of dispersal distance of non-native Phragmites based on model simulations

• Soons, M.B. (2006), Wind dispersal in freshwater wetlands: knowledge for conservation and restoration. Applied Vegetation Science, 9(2): 271-278.

Invasion risk factors

Water levels and salinity

Non-native Phragmites establishes on well-drained sites and translocates oxygen to the invasion front

• Bart, D. & Hartman, J. M. (2000), Environmental determinants of Phragmites australis expansion in a New Jersey salt marsh: an experimental approach. Oikos, 89: 59-69.

An increase in the number of sites colonized by non-native Phragmites from 1980-2002 is attributed to low water table levels of the Saint Lawrence river in the mid to late 90s

• Hudon, C., Gagnon, P., & Jean, M. (2005), Hydrological factors controlling the spread of common reed (Phragmites australis) in the St Lawrence River (Québec, Canada). Écoscience, 12: 347–357.

Rate of spread of non-native Phragmites in Great Lakes coastal wetlands; exposed mudflats from receding water tables facilitate invasion

• Tulbure, M.G., Johnston, C.A., & Auger, D.L. (2007), Rapid invasion of a Great Lakes coastal wetland by non-native Phragmites australis and Typha. Journal of Great Lakes Research, 33 (sp3), 269-279.
• Tulbure, M.G., & Johnston, C.A. (2010), Environmental conditions promoting non-native Phragmites australis expansion in Great Lakes coastal wetlands. Wetlands, 30(3): 577-587.

Water levels and salinity affect the ability of non-native Phragmites to invade tidal wetlands

• Chambers, R.M., Osgood, D.T., Bart, D.J. et al. (2003), Phragmites australis invasion and expansion in tidal wetlands: interactions among salinity, sulfide, and hydrology. Estuaries, 26: 398–406.
• Warren, R.S., Fell, P.E., Grimsby, J.L. et al. (2001), Rates, patterns, and impacts of Phragmites australis expansion and effects of experimental Phragmites control on vegetation, macroinvertebrates, and fish within tidelands of the lower Connecticut River. Estuaries, 24(1): 90-107.

Establishment of non-native Phragmites occurs throughout the marsh continuum but there is a greater frequency of establishment within 5m of the creek bank

• Lathrop, R.G., Windham, L., & Montesano, P. (2003), Does Phragmites expansion alter the structure and function of marsh landscapes? Patterns and processes revisited. Estuaries, 26(2): 423-435.

Disturbance

Non-native Phragmites increases under the Cumulative Stress Index which incorporates five types of anthropogenic stress

• Johnston, C.A., Ghioca, D.M., Tulbure, M., Bedford, B.L., Bourdaghs, M., Frieswyk, C.B., Vaccaro, L., & Zedler, J.B. (2008), Partitioning vegetation response to anthropogenic stress to develop multitaxa wetland indicators. Ecological Applications, 18: 983-1001.

Disturbance of the marshes around the Great Salt Lake improves growth of non-native Phragmites

• Kulmatiski, A., Beard, K.H., Meyerson, L.A., Gibson, J.R., & Mock, K.E. (2011), Non-native Phragmites australis invasion into Utah Wetlands. Western North American Naturalist, 70(4): 541-552.

Non-native Phragmites seeds are able to establish in small high marshes disturbed by humans or mammals

• Kettenring, K.M., Whigham, D.F., Hazelton, E.L., Gallagher, S.K., & Weiner, H.M. (2015), Biotic resistance, disturbance, and mode of colonization impact the invasion of a widespread, introduced wetland grass. Ecological Applications, 25: 466-480.

Roads and salinity

Non-native Phragmites invasion inland coincides with the intensification of road networks, which establishes linear wetlands with high connectivity

• Brisson, J., de Blois, S., & Lavoie, C. (2010), Roadside as invasion pathway for common reed (Phragmites australis). Invasive Plant Science and Management, 3(4):506-514.

An underlying factor in expansion of non-native Phragmites is its greater salinity tolerance than native Phragmites

• Vasquez, E., Glenn, E., Brown, J., Guntenspergen, G., & Nelson, S. (2005), Salt tolerance underlies the cryptic invasion of North American salt marshes by an introduced haplotype of the common reed Phragmites australis (Poaceae). Marine Ecology Progress Series, 298: 1-8.

Roadsides in Quebec are highly invaded because non-native Phragmites is able to withstand de-icing salt more than other native plants, and the road ditches are highly interconnected and expansive

• Lelong, B., Lavoie, C., Jodoin, Y., & Belzile, F. (2007), Expansion pathways of the exotic common reed (Phragmites australis): a historical and genetic analysis. Diversity and Distributions, 13: 430-437.

Highways/roads are corridors for dispersal and roadside ditches provide habitat for non-native Phragmites because of elevated salinity and nutrients

• Jodoin, Y., Lavoie, C., Villeneuve, P., Theriault, M., Beaulieu, J., & Belzile, F. (2008), Highways as corridors and habitats for the invasive common reed Phragmites australis in Quebec, Canada. Journal of Applied Ecology, 45: 459-466.
• Bellavance, M.E., & Jacques, B. (2010), Spatial dynamics and morphological plasticity of common reed (Phragmites australis) and cattails (Typha sp.) in freshwater marshes and roadside ditches. Aquatic Botany, 93(2):129-134.

Eutrophication

Shoreline development removes the woody vegetation buffer between terrestrial and salt marsh plant communities, which causes nitrogen eutrophication that then facilitates non-native Phragmites invasion

• Bertness, M.D., Ewanchuk, P.J., & Silliman, B.R. (2002), Anthropogenic modification of New England salt marsh landscapes. Proceedings of the National Academy of Sciences, 99(3): 1395-1398.

Watershed development and elevated nutrients facilitate non-native Phragmites invasion

• King, R.S., Deluca, W.V., Whigham, D.F. et al. (2007), Threshold effects of coastal urbanization on Phragmites australis (common reed). Estuaries and Coasts, 30(3): 469–481.

Disturbances that remove native vegetation and increase nutrient load to soil facilitate spread of non-native Phragmites

• Minchinton, T.E., & Bertness, M.D. (2003), Disturbance‐mediated competition and the spread of Phragmites australis in a coastal marsh. Ecological Applications, 13:1400-1416.

Agriculture was the strongest and most consistent predictor of non-native Phragmites presence and abundance in Chesapeake Bay. Phragmites can exploit the elevated nutrient levels with increased establishment, growth, and seed production

• Sciance, M.B., Patrick, C.J., Weller, D.E. et al. (2016), Local and regional disturbances associated with the invasion of Chesapeake Bay marshes by the common reed Phragmites australis. Biological Invasions, 18(9): 2661-2677.

Non-native Phragmites can take advantage of increased nutrient availability more than native Phragmites

• Saltonstall, K., & Stevenson, J.C. (2007), The effect of nutrients on seedling growth of native and introduced Phragmites australis. Aquatic Botany, 86(4): 331-336.
• Mozdzer, T.J., Zieman, J.C., & McGlathery, K.J. (2010), Nitrogen uptake by native and invasive temperate coastal macrophytes: importance of dissolved organic nitrogen. Estuaries and Coasts, 33(3): 784-797.
• Price, A.L., Fant, J.B., & Larkin, D.J. (2014), Ecology of native vs. introduced Phragmites australis (common reed) in Chicago-area wetlands. Wetlands, 34(2): 369-377.
• Hunt, V.M., Fant, J.B., Steger, L. et al. (2017), PhragNet: crowdsourcing to investigate ecology and management of invasive Phragmites australis (common reed) in North America Wetlands. Ecology Management, 25(5): 607-618.

Global Change

Climate change is allowing non-native Phragmites seedlings to germinate and survive through the winter

• Brisson, J., Paradis, E., & Bellavance, M. (2008), Evidence of Sexual Reproduction in the Invasive Common Reed (Phragmites australis subsp. australis; Poaceae) in Eastern Canada: A Possible Consequence of Global Warming. Rhodora, 110(942):225-230.

In response to elevated carbon dioxide and nitrogen, non-native Phragmites outperformed native Phragmites across nearly every response trait measured (both above- and below-ground) and by a factor of 2-3 under every global change scenario.

• Mozdzer, T. J., and J. P. Megonigal. 2012. Jack-and-master trait responses to elevated CO2 and N: a comparison of native and introduced Phragmites australis. PLOS ONE 7:e42794.

Miscellaneous

North American native clones were suppressed by North American invasives as well as by European native clones, but there was no effect of ploidy level on competition.

• Pysek, P., Cuda, J., Smilauer, P., Skalova, H., Chumova, Z., Lambertini, C., Lucanova, M., Rysava, H., Travinicek, P., Semberova, K., Meyerson, L.A., (2019). Competition among native and invasive Phragmites australis populations: An experimental test of the effects of invasion status, genome size, and ploidy level. Ecology and Evolution, 10:1106-1118.

Bacterial and fungal isolates did not discriminate between native and non-native Phragmites hosts.

• DeVries, A.E., Kowalski, K.P., and Bickford, W.A. (2020). Growth and Behavior of North American Microbes on Phragmites australis Leaves. Microorganisms.

Reduce native plant community vulnerability to invasion by manipulating nutrients (nitrogen)

• Uddin, M.N., Robinson, R.W., Asaeda, T. (2020). Nitrogen immobilization may reduce invasibility of nutrient enriched plant community invaded by Phragmites australis. Scientific Reports, 2020-01-31, 10(1):1601-1616.

Pathogen damage was similar between native and invasive lineages of Phragmites in common garden culture.

• Warwick, A.J., DeVries, A.E., Bologna, N.J., Bickford, W.A., Kowalski, K.P., Meyerson, L.A., Cronin, J.T., Moles, A. 2020. Intraspecific and biogeographical variation in foliar fungal communities and pathogen damage of native and invasive Phragmites australis. Global ecology and biogeography, 29(7): 1199-1211.

Effects on biodiversity

Non-native Phragmites excludes native forbs through direct competition and accumulation of thick litter layers

• Minchinton, T.E., Simpson, J.C., & Bertness, M.D. (2006), Mechanisms of exclusion of native coastal marsh plants by an invasive grass. Journal of Ecology, 94:342–354.

Impacts of non-native Phragmites in Tidal Wetlands

• Chambers R.M., Meyerson L.A., Dibble K.L. (2012) Ecology of Phragmites australis and Responses to Tidal Restoration. In: Roman C.T., Burdick D.M. (eds) Tidal Marsh Restoration. The Science and Practice of Ecological Restoration. Island Press, Washington, DC.

Non-native Phragmites invasion in brackish tidal marshes reduces invertebrates and impairs fish use and support

• Able, K. W., and S. M. Hagan. 2000. Effects of common reed (Phragmites australis) invasion on marsh surface macrofauna: response of fishes and decapod crustaceans. Estuaries 23:633-646.
• Able, K. W., S. M. Hagan, and S. A. Brown. 2003. Mechanisms of marsh habitat alteration due to Phragmites: response of young-of-the-year Mummichog (Fundulus heteroclitus) to treatment for Phragmites removal. Estuaries 26:484-494.
• Able, K.W. & Hagan, S.M. (2003), Impact of common reed, Phragmites australis, on essential fish habitat: Influence on reproduction, embryological development, and larval abundance of mummichog (Fundulus heteroclitus). Estuaries, 26(1): 40-50.

Phragmites invasion in New England tidal marshes is detrimental to marsh bird populations

• Benoit, L.K. & Askins, R.A. (1999), Impacts of the spread of Phragmites on the distribution of birds in Connecticut tidal marshes. Wetlands, 19(1): 194-208.

Non-native Phragmites provides only marginal habitat for several breeding marsh-nesting bird species

• Meyer, SW., Badzinski, S.S., Petrie, S.A., & Davison, C. (2010), Seasonal abundance and species richness of birds in common reed habitats in Lake Erie. Ankney Journal of Wildlife Management, 74(7):1559-1567.

Phragmites chemically deterred the marsh periwinkle snail Littoraria irrorata

• Hendricks, L.G., Mossop, H.E., & Kicklighter, C.E. (2011), Palatability and chemical defense of Phragmites australis to the marsh periwinkle snail Littoraria irrorata. Journal of Chemical Ecology, 37:838.

Effects on ecosystem processes

Phragmites-invaded areas had ~10x the live aboveground biomass of uninvaded areas and less microtopographic relief. These factors correlated with Phragmites stand age and stabilized in 8-15 year old stands

• Windham, L., & Lathrop, R.G. (1999), Effects of Phragmites australis (common reed) invasion on aboveground biomass and soil properties in brackish tidal marsh of the Mullica River, New Jersey. Estuaries, 22(4): 927-935.

Phragmites invasion alters nitrogen cycling in northeastern tidal marshes

• Windham, L. and Ehrenfeld, J. G. (2003), Net impact of a plant invasion on nitrogen‐cycling processes within a brackish tidal marsh. Ecological Applications, 13: 883-896.
• Windham, L. & Meyerson, L.A. (2003), Effects of common reed (Phragmites australis) expansions on nitrogen dynamics of tidal marshes of the northeastern U.S. Estuaries, 26:452-464.

Phragmites invasion can increase greenhouse gas fluxes

• Brix, H., B. K. Sorrell, and B. Lorenzen. 2001. Are Phragmites-dominated wetlands a net source or net sink of greenhouse gases? Aquatic Botany 69:313-324.

Mozdzer, T. J., and J. P. Megonigal. 2013. Increased methane emissions by an introduced Phragmites australis lineage under global change. Wetlands 33:609-615.

Where to target control efforts

Target control efforts on non-native Phragmites patches in areas of higher exposure to wave energy because those have higher density of seedlings

• Baldwin, A.H., Kettenring, K.M., & Whigham, D.F. (2010), Seed banks of Phragmites australis-dominated brackish wetlands: relationships to seed viability, inundation, and land cover. Aquatic Botany, 93(3):163-169.

Target control efforts on small non-native Phragmites patches before they accumulate sufficient genetic variation for viable seed production. Also reduced nutrient inputs into watersheds to help limit reproductive output

• Kettenring, K.M., & Adams, C.R. (2011), Lessons learned from invasive plant control experiments: a systematic review and meta‐analysis. Journal of Applied Ecology, 48: 970-979.

Probability of eradicating non-native Phragmites is higher in smaller patches than in larger patches

• Quirion, B., Simek, Z., Dávalos, A. et al. (2018), Management of invasive Phragmites australis in the Adirondacks: a cautionary tale about prospects of eradication. Biological Invasions, 20(1): 59-73.

Control strategies

Herbicide

Imazapyr provided somewhat better control of non-native Phragmites than glyphosate: 93% vs. 82% reduction, respectively, averaged across applications in both June and September

• Derr, J.F. (2008), Common Reed (Phragmites australis) Response to postemergence herbicides. Invasive Plant Science and Management, 1(2):153-157.

Glyphosate was more effective at reducing non-native Phragmites percent cover when applied in June than when applied in September. Imazapyr applied early in the growing season may be up to 20% more effective. The difference in percent cover reduction between September and June application was greater for glyphosate than imazapyr

• Mozdzer, T.J., Hutto, C.J., Clarke, P.A., & Field, D.P. (2008), Efficacy of imazapyr and glyphosate in the control of non-native Phragmites australis. Restoration Ecology, 16: 221-224.

Application of glyphosate and imazapyr together reduced non-native Phragmites frequency of occurrence by 48% and cover by >75%. Glyphosate application alone did not change the frequency of occurrence or percent cover of non-native Phragmites but did prevent these measures from increasing

• Getsinger, K.D., Poovey, A.G., Kafcas, E., & Schafer, J. (2013), Chemical control of invasive Phragmites in a Great Lakes marsh: a field demonstration. Army Corps of Engineers ERDC/EL TN-13-1, pgs 1-16.

Non-native Phragmites was not eliminated from all sites after 7 years of herbicide treatment. However, the proportion of swales described as having only light invasion or no invasion increased from 68% to 90% over this period.

• Lombard, K.B., Tomassi, D., & Ebersole J. (2012), Long-term management of an invasive plant: lessons from seven years of Phragmites australis control. Northeastern Naturalist, 19(6): 181-193.

Imazapyr provided the highest control of Phragmites across all treatment timings and imazamox provided the lowest. Imazapyr and glyphosate, when applied alone or together, provided ~90% control by the end of the first growing season and into the next growing season (390 to 450 days post-treatment) regardless of application timing. Phragmites stem density decreased across all herbicide treatments and timings except in the case of imazamox applied during the vegetative growth stage

• Knezevic, S.Z., Rapp, R.E., Datta, A., & Irmak, S. (2013), Common reed (Phragmites australis) control is influenced by the timing of herbicide application. International Journal of Pest Management, 59(3): 224-228.

Application of glyphosate prior to non-native Phragmites seed set can reduce addition of viable seeds to the seedbank

• Howell, G.M.B, (2017), Best management practices for invasive Phragmites control. Waterloo, Ontario, Canada, MS thesis.

Herbicide + physical removal (mowing/cutting/burning)

Native plant re-growth was faster when Phragmites was treated with herbicide in the fall and burned because more Phragmites biomass was cleared

• Ailstock, M.S., Norman, C.M., & Bushmann, P.J. (2001), Common reed Phragmites australis: control and effects upon biodiversity in freshwater nontidal wetlands. Restoration Ecology, 9: 49-59.

After seven years of glyphosate and imazapyr application combined with mowing, non-native Phragmites percent cover decreased by 60%

• Back, C.L., & Holomuzki, J.R. (2008), Long-term spread and control of invasive, common reed (Phragmites australis) in Sheldon Marsh, Lake Erie. The Ohio Journal of Science, 108(5):108-112.

Cutting and raking in combination with glyphosate application were most effective at limiting non-native Phragmites growth. Litter removal in early summer increased emergence of other wetland species and reduced growth of non-native Phragmites stands

• Carlson, M.L., Kowalski, K.P., & Wilcox, D.A. (2009), Promoting species establishment in a Phragmites-dominated Great Lakes coastal wetland. Natural Areas Journal, 29(3):263-280.

Glyphosate treatment of non-native Phragmites followed by mowing two weeks post-treatment reduced Phragmites by 90% relative to control treatment

• Derr, J.F. (2007), Common Reed (Phragmites australis) Response to Mowing and Herbicide Application. Invasive Plant Science and Management, 1(1):12-16.

Three years of mowing and herbicide treatments yielded significantly lower mean densities of non-native Phragmites than hand-cutting and herbicide-only treatments. Native plant species richness increased in both treatments but significantly more so in the mowing + herbicide treatment

• Farnsworth, E.J., & Meyerson, L.A. (1999), Species composition and inter-annual dynamics of a freshwater tidal plant community following removal of the invasive grass, Phragmites australis. Biological Invasions, 1: 115-127.

After five years of treatment with glyphosate and cutting, the percent cover of non-native Phragmites decreased from 100% to <10% cover and native plants increased from 0% cover to >80% cover and the amount of herbicide used decreased

• Hallinger, K.D., & Shisler, J.K. (2009), Seed bank colonization in tidal wetlands following Phragmites control (New Jersey). Ecological Restoration, 27:16–18.

Recommendation to mow Phragmites in summer and apply glyphosate in the fall. See figure 1

• Kettenring, K.M., Rohal, C.B., Cranney, C., & Hazelton, E.L.G. (2014), Assessing approaches to manage Phragmites in Utah wetlands. Final report to the Utah Division of Wildlife Resources, Division of Wildlife Resources. 12 pp.

Percent cover of non-native Phragmites was reduced from 77% in untreated plots to 15% in treated plots. An integrated approach of herbicide followed by burning is recommended

• Moore, G.E., Burdick, D.M., Buchsbaum, R., & Peter, C.R. (2012), Investigating causes of Phragmites australis colonization in Great Marsh, Parker River National Wildlife Refuge. Final Report prepared for Massachusetts Bays Program, Boston, MA.pp. 36.

Disking and mowing alone provided control for only a few months. Control was significantly prolonged (at least three seasons) when disking and mowing were combined with herbicide

• Rapp, R.K., Datta, A., Irmak, S., Arkebauer, T.J., & Knezevic, S.Z. (2012), Integrated management of common reed (Phragmites australis) along the Platte River in Nebraska. Weed Technology, 26(2): 326-333.

To limit post-control reinvasion, seed set in areas not being treated with herbicide should be prevented by removing flowering culms.

• Galatowitsch, S. M., D. L. Larson, and J. L. Larson. 2016. Factors affecting post-control reinvasion by seed of an invasive species, Phragmites australis, in the central Platte River, Nebraska. Biological Invasions 18:2505-2516.

Other treatments (cutting only, grazing)

Cutting followed by flooding reduced above-ground growth and survival. Density, height, and biomass of non-native Phragmites were all decreased with increasing salinity (to 15 and 30 g/l). Manipulating water and salinity levels may be useful for controlling Phragmites

• Hellings, S.E., & Gallagher, J.L (1992), The effects of salinity and flooding on Phragmites australis. Journal of Applied Ecology, 29:41–49.

Goat grazing reduced non-native Phragmites percent cover

• Silliman, B.R., Mozdzer, T., Angelini, C., Brundage, J.E., Esselink, P., Bakker, J.P., Gedan, K.B., van de Koppel, J., & Baldwin, A.H. (2014), Livestock as a potential biological control agent for an invasive wetland plant. PeerJ, 2:e567.
• Brundage, A. (2010), Grazing as a management tool for controlling Phragmites australis and restoring native plant biodiversity in wetlands. College Park, MD, USA MS Thesis.

Livestock grazing and herbicide application can be integrated for non-native Phragmites management

• Rohal, C., Hambrecht, K., Cranney, C., & Kettenring, K. (2017), How to restore Phragmites-invaded wetlands. Utah Agricultural Experiment Station Research Report 224, Logan, UT. 2pp.

Biotic resistance from plant diversity

Native annual plants exhibited high biotic resistance to Phragmites invasion, and biotic resistance was greater with higher functional group diversity

• Byun, C., Blois, S., Brisson, J., & Cornwell, W. (2013), Plant functional group identity and diversity determine biotic resistance to invasion by an exotic grass. Journal of Ecology, 101:128-139.

The presence of native competitors greatly reduced the aboveground biomass of non-native Phragmites (83.7%)

• Peter, C.R., & Burdick, D.M. (2010), Can plant competition and diversity reduce the growth and survival of exotic Phragmites australis invading a tidal marsh? Estuaries and Coasts, 33(5): 1225-1236.

Responses of wetland ecosystems and organisms to Phragmites control

Removal of Phragmites enabled regrowth of a more diverse plant community but patterns in ammonium accumulation and denitrification suggest a reduction in the capacity of marsh to act as a sink for nitrogen

• Findlay, S., Groffman, P., & Dye, S. (2003), Effects of Phragmites australis removal on marsh nutrient cycling. Wetlands Ecology and Management, 11:157-165.

Herbicide treatments (glyphosate and imazapyr) did not affect snail taxon richness (concurrent with 90% reduction in non-native Phragmites percent cover following one year of herbicide application)

• Back, C.L., Holomuzki, J.R., Klarer, D.M. et al. (2012), Herbiciding invasive reed: indirect effects on habitat conditions and snail–algal assemblages one year post-application. Wetlands Ecology and Management, 20(5): 419-431.

Spartina and associated arthropod communities reassembled into marsh 5 years after fall spraying of non-native Phragmites with glyphosate

• Gratton, C., & Denno, R.F. (2005), Restoration of arthropod assemblages in a Spartina salt marsh following removal of the invasive plant Phragmites australis. Restoration Ecology, 13: 358-372.

Measuring change in nekton abundance between sites dominated by invasive Phragmites vs. areas that were treated

• Kimball M.E., & Able K.W. (2007), Nekton utilization of intertidal salt marsh creeks: tidal influences in natural Spartina, invasive Phragmites, and marshes treated for Phragmites removal. Journal of Experimental Marine Biology and Ecology, 346: 87-101.

Large-scale aerial herbicide applications to manage Phragmites was associated with reduced productivity of marsh wrens in coastal study marshes

• Lazaran, C., Bocetti, I., & Whyte, R.S. (2013), Impacts of Phragmites management on marsh wren nesting behavior. The Wilson Journal of Ornithology, 125 (1): 184-187.

Richness and diversity were greater in wetlands managed to control invasive Phragmites with herbicide or prescribed burns compared to no management

• Bonello, J.E., Judd, K.E., 2020, Plant community recovery after herbicide management to remove Phragmites australis in Great Lakes coastal wetlands. Restoration Ecology, 28(1):215-221.

Overviews and syntheses of Phragmites management

Cross-institutional economic survey of 285 land managers from US public and private conservation organizations. Despite high expenditures, few organizations achieved management goals. No relationship between resources invested and management effectiveness. Results call into question effectiveness of current management strategies

• Martin, L.J., & Blossey, B. (2012), The runaway weed: costs and failures of Phragmites australis management in the USA. Estuaries and Coasts, 36: 626-632.

Review of 40 years of Phragmites management found: little information on recovery of vegetation following removal of Phragmites and most management approaches focus on removal of Phragmites from individual stands over a relatively small area. Recovery studies were not conducted in a landscape context. Phragmites management needs to shift to watershed-scale efforts in coastal regions, or larger management units inland. Management efforts should focus on restoring native plant communities, not just removing Phragmites. Wetlands and watersheds should be prioritized to identify ecosystems that would benefit most from Phragmites management.

• Hazelton, E. L., T. J. Mozdzer, D. M. Burdick, K. M. Kettenring, and D. F. Whigham. 2014. Phragmites australis management in the United States: 40 years of methods and outcomes. AoB Plants 6:plu001.

Monitoring requirements and procedures for effective non-native Phragmites management. Addresses biological control, burning, use of plastic mulch, disking, chemical control, cutting, grazing, dredging and draining, and manipulation of water table and salinity

• Marks, M., Lapin, B., & Randall, J. (1994). Phragmites australis (P. communis): threats, management and monitoring. Natural Areas Journal. 14:285-294.

Overview of best management practices for non-native Phragmites

• Ontario Ministry of Natural Resources, Invasive Phragmites – Best Management Practices, Ontario Ministry of Natural Resources, Peterborough, Ontario. Version 2011. 15p.