Phragmites australis: A major invasive threat to Great Lakes coastal habitats

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1 Phragmites australis: A major invasive threat to Great Lakes coastal habitats J.M. Gilbert, Ph.D., Ecologist, Ontario Parks Frank Letourneau, Dover Agri-Serve Canada/Ontario Agreement Respecting the Great Lakes Ecosystem

2 Some facts: Phragmites australis - common reed, giant reed Native species- uncommon member of wetland plant communities in North America for at least 3000 yrs Last few decades noticeable increase in Phragmites populations- monocultures Issue first realized along Eastern Seaboard ~1970 s It s like this grass is on steroids or something! Broadway Danny Rose 1984

3 Some facts cont d: Since mid 1980 s noticed along St. Lawrence, Great Lakes coastal areas Reduced biodiversity, hydrological alterations, nutrient cycling changes Population explosion thought to be linked to land use changes- increased disturbance, hydrological changes, urbanization, eutrophication Recent genetic research indicates invasive haplotype M Phragmites australis subsp. australis

4 Some facts cont d: Spreads into new areas through seed dispersal and rhizomes especially in disturbed sites ~2,000 seeds/head; low germination rate; germination occurs on moist, bare soil Once established spreads predominantly underground via rhizomes; dense clones ~200 stems/m 2

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6 Turkey Point Phragmites Trial Plots-2010

7 Turkey Point Phragmites Test Plots

8 Turkey Point Phragmites Test Plots-2010

9 Turkey Point Phragmites Test Plots A total of 43 plots were sampled throughout the Phragmites dominated community along Ordnance Beach, Turkey Point Provincial Park.

10 Turkey Point Phragmites Test Plots A total of 60 species were observed throughout the sampled area. Of these, 13 are non-native including 4 invasives Lythrum salicaria (purple loosestrife), Phalaris arundinacea (reed canary grass), Typha angustifolia (narrow-leaved cattail) and Phragmites. These species are all known to out-compete other species thereby reducing diversity and habitat value through expansion into large mono-culture communities.

11 Turkey Point Phragmites Test Plots Invasive Phragmites was by far the most frequently observed plant with a presence in 42 of the 43 sampled plots. The next most commonly observed species was Scirpus americanus (Common three square) which was observed in 28 plots. The remaining species were present in 15 or fewer plots and of these, 19 species were only seen in one plot each.

12 Phragmites australis subsp. australis Scirpus americanus Lycopus uniflorus Convolvulus arvensis Eleocharis sp. Salix sp. Cornus stolonifera, Poacea Impatiens capensis, Salix eriocephale, Carex lacustris, Leersia oryzoides, Eupatorium perfoliatum, Verbena hastata Cyperus sp., Solidago sp. Carex vulpinodea, Juncus nodosus, Potentilla Bidens cernua, Calamagrostis canadensis, Cicuta bulbifera, Cirsium sp., Eupatorium Epilobium sp., Equisetum sp., Glyceria sp., Iris 19 species total # of plots species observed in Turkey Point Phragmites Test Plots Species observed

13 Turkey Point Phragmites Test Plots With the exception of Phragmites, the frequency with which certain species were observed was not relative to percent coverage. For instance, although Scirpus americanus (common three-square) was observed within 28 sample plots it only represented 2.3% of total coverage. Conversely, the unidentified grasses (Poacea spp.) and Calamagrostis canadensis (Canada blue joint) were observed within only 11 and 4 plots respectively but, covered 4.6% and 4.2% of the total sampled area which represented the highest coverage after Phragmites. The next most abundant species was willow (Salix sp.) with ~ 3.5% while 50 species had less than 1% coverage for the entire area sampled and these collectively covered only ~9%. Not surprisingly, invasive Phragmites dominated all but 7 of the 43 sample plots with ~100% coverage in 8 plots and 80% or more coverage in 23 plots. For all 43 plots combined, Phragmites represented ~70% of the total area sampled.

14 Turkey Point Phragmites Test Plots Cornus stolonifera, 1.28 Salix eriocephale, 1.49 Solidago canadensis, 1.81 Phalaris arundinacea, 2.07 Scirpus americanus, 2.3 Salix sp., 3.65 Glyceria sp., species, 9.02 Calamagrostis canadensis, 4.19 Poacea, 4.60 Phragmites australis subsp. australis, 68.28

15 Turkey Point Phragmites Test Plots-2010

16 Turkey Point Phragmites Test Plots 2010

17 Turkey Point Phragmites Test Plots -2010

18 Turkey Point Phragmites Test Plots-2010

19 Turkey Point Phragmites Test Plots

20 Turkey Point Phragmites Test Plots

21 Control Options Mechanical control: burning, cutting, drowning, smothering Livestock grazing: cattle, sheep, goats Biological: herbivores in Europe; 40% feed only on Phragmites - 26 herbivores known to attack Phragmites in the U.S. - all but 5 introduced - 4 moths recently identified as potentially effective (Dr. Blossey, Cornell University; XHarpSPAH@aol.com) Chemical control: Glyphosate (Roundup, Rodeo), Imazapyr (Habitat) - Spraying, injection, handwicking

22 Round Up Active ingredient Glyphosate: Roundup Ultra II, Weathermax (Monsanto) White, crystalline organophosphate salt (C 3 H 8 NO 5 P) extremely broad spectrum plant mortality primarily due to the inability of most plant species to rapidly metabolize the chemical to non-toxic forms readily absorbed into the treated plants from the leaves to the roots and shoot apices where the meristematic growth cells are located the chemical inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) which is a key enzyme in the shikimate biosynthetic pathway enzyme is essential in the production of aromatic amino acids, auxin, phytoalexins, folic acid, lignin, plastoquinones and numerous secondary products required by plants particular chemical is relatively harmless to animals since they lack the shikimate pathway

23 The issues Within expansive Phragmites stands (>.25 ha) wildlife were absent (no nests, tracks, scat or other evidence of use) Native plant species cannot compete with Phragmites The loss of habitat for numerous Species at Risk and other wetland dependent wildlife will be extensive if this invasive plant is left unchecked

24 The issues cont d Control of both Phragmites and cattail has been occurring in dry municipal ditches throughout Southwestern Ontario over the past 20 years using glyphosate products Licenced pesticide applicators can legally use Roundup Ultra II to target Phragmites in wetlands and on beaches as long as surface water is not present during time of application Cosmetic Pesticide ban- a requirement to obtain a written opinion from the district OMNR to use a chemical on non-provincial government properties

25 The issues cont d URMULE (User Requested Minor Use Label Expansion) application required by the Pest Management Regulatory Agency (PMRA) to include Phragmites on labels of Roundup Ultra II, Weathermax, and Vision for legal application throughout Canada- Approved July 2010 The most effective control methods known are not currently legal options in Canada (aerial/over water application of glyphosate)

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30 Phragmites Control Pilot Projects 1) Testing efficacy of Roundup vs. grass select herbicides - Experimental plots 2) Roundup spraying in difficult to access, sensitive, habitats 3) Mechanical control- cutting/flooding

31 Phragmites Control Pilot Projects: Locations Ontario Hamilton London Windsor Lake Erie Phragmites Control Pilot Projects Lake Erie Rondeau Bay Rondeau Provincial Park

32 Pilot Project: Experimental plots- grass specific herbicides 8 herbicides (including Roundup Ultra II), vinegar, control 2 methods: spray and injection 120 1x1m 2 plots 6 replicates per treatment Percentage of Species Present in 120 Marsh Trail Plots Other Species Phragmites (Live) 28% (26 spp.) 3% Phragmites (Dead) 69%

33 What we have learned: Grass specific herbicides are not as effective as Roundup Ultra II in controlling Phragmites (spray treatments) Roundup Ultra II does not appear to reduce plant species diversity Chemical translocation through connected belowground structures was not evident in injection treatments Most effective injection product was vinegar (%5 or 25% acetic acid)

34 Pilot Project: Phragmites control by spraying Roundup in difficult to access, sensitive, habitats McLean and Bates Wetlands, Rondeau Bay

35 McLean Marsh, Rondeau Bay, 2007 What we have learned: In well established Phragmites communities native plants are rarely observed Diversity in Phragmites Communities McLean Marsh > 5m in height Phragmites, 96.9% other, 3.1%

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37 What we have learned: cont d Conventional spray equipment is not appropriate for use in most natural systems Stuck!!!, McLean Marsh 2007

38 What we have learned: cont d A retrofitted ARGO is highly effective and efficient in certain habitats Rondeau Bay 2008

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41 What we have learned: cont d Roundup Ultra sprayed at a 5% concentration on mature plants can control ~85% of densely populated stand after 1 treatment McLean Marsh, Rondeau Bay, Pre-treatment, 2007 McLean Marsh, Rondeau Bay, Post-treatment, 2008

42 What we have learned: cont d Controlling Phragmites with Roundup Ultra II does not appear to adversely affect native plant species recovery 15 other spp., 7.5% Impatiens, 6.6% Phalaris, 10% Phragmites, 17.2% Typha spp., 58.7% Cattail, bulrush, sedge, arrowhead, wild rice, McLean Marsh, August 2008

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44 What we have learned: cont d Removal of biomass appears to improve native plant species response and allows for easier follow-up Phragmites control McLean Marsh, Rondeau Bay, 2007

45 What we have learned: cont d Rolling standing dead Phragmites stalks prior to burning is safer, reduces seed residue, promotes drowning McLean Marsh, Rondeau Bay, 2007

46 What we have learned: cont d Controlling Phragmites by cutting and flooding may be a non-chemical option where feasible Pilot Project : Experimental plot testing mechanical control, Rondeau Bay

47 What we have learned: cont d Injection and/or hand wicking will control Phragmites in low density stands where spraying is not a safe option Hand wicking Rhizome injection Sauble Beach, October 2008

48 What we have learned: cont d Public education (signage, flyers, local paper articles/notices, meetings) is essential Public participation is key for successful long term Phragmites management due to recurring invasions Sauble Beach October 2008

49 Next Steps?

50 Recommended Next Steps: Require experienced advocate (forestry sector?) to pursue legal approvals for aerial and over water herbicide Phragmites control options in Canada Secure funding to support required initiatives and on the ground control efforts Establish Province wide Phragmites control program to determine extent of invasion and target valuable, at risk habitats as first priority (crown or privately owned) Establish Phragmites Technical Team: mandate to assist with proposed Phragmites control projects from an ecological, legal, logistical, and public relations perspective