Early Detection & Rapid Response to Stiltgrass in Washtenaw County

Transcription

1 Early Detection & Rapid Response to Stiltgrass in Washtenaw County Becky Gajewski City of Ann Arbor Natural Area Preservation Katie Carlisle Washtenaw County Parks & Recreation Commission

2 What is Stiltgrass? An annual grass native to China, India, Japan, Korea, and Malaysia Introduced to North America in 1919 in Tennessee Used as packing material for porcelain Grows in floodplain forests, forest edges, damp fields and lawns, and on streambanks and road and trail edges Very tolerant of shade Photo: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

3 Resembles a small, delicate bamboo with weak roots and a sprawling habit Leaves are 1-3 inches long with an offcenter, shiny midrib Most native grasses feel rough in one direction when rubbed, but stiltgrass feels smooth in both Aerial roots form near the base, resembling stilts Tops of the plant turn purple or brown in the fall, giving the plant the alternate name Nepalese browntop Resembles and often grows with native whitegrass (Leersia virginica)

4 Photo: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org Photo: Chris Evans, University of Illinois, Bugwood.org

5 Why is it a Problem? Rapidly forms dense monocultures and crowds out native vegetation Produces lots of seeds, which are easily transported by water and wildlife Thatch burns very hot, making controlled fire a difficult tool to use Alters light and soil regimes, nutrient cycling, and likely affects native seed germination Suppresses insect communities Not a preferred food for grazers Photos: Chris Evans, University of Illinois, Bugwood.org

6 Why is it a Problem? Photos: Chris Evans, University of Illinois, Bugwood.org

7 An Established Problem

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10 Our Story Begins in 2017 Stiltgrass is found on a private property between Dexter and Ann Arbor Possibly the first sighting of stiltgrass in Michigan? Quick identification allowed for quick action Local stewardship community mobilized Neighboring properties were searched Eradication and a pat on the back!

11 But in 2018 WASHTENAW COUNTY CITY OF ANN ARBOR Stiltgrass is found on a Legacy Land Conservancy easement just outside of Ann Arbor Following the footprint of the infestation revealed that it was also on a City of Ann Arbor conservation easement and a Washtenaw County Preserve.

12 The Strike Team Assembles! Realizing this may be a bigger problem than initially thought, the local conservation community came together to discuss next steps. The initial goal was to eradicate, or at least contain the invasion. Legacy Land Conservancy City of Ann Arbor Natural Area Preservation Washtenaw County Parks and Recreation Michigan Department of Natural Resources Stewardship Network Huron River Watershed Council WildOnes Ann Arbor The new Jackson, Lenawee & Washtenaw CISMA

13 Citizen Engagement Volunteers continued finding stiltgrass in the neighborhood where the invasion was initially found Informational brochure developed and mailed to over 600 people in the hot zone, asking them to look for and report stiltgrass Dedicated and Google voice accounts created Door hanger developed, and interns/volunteers went doorto-door to houses believed to have stiltgrass or be immediately threatened

14 Determining the Extent We received permission from neighbors responding to the brochure to map on private lands Volunteers went out with GPS units Engagement with other neighbors while out mapping Word of mouth travelled fast Results were put into an online map all partners could access

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16 Shifting Goals

17 Cultivating Support This is definitely a bigger problem than we first thought! How do we move forward? Are we in over our heads? How do we treat all of this private land? Pursuing funding from DTE and ITC and assistance from JLW CISMA Purchasing herbicide and application equipment Hiring contractors Other funding sources?

18 Increasing Awareness Public meeting August 15 for neighbors of hot zone and interested citizens Sign up to volunteer and/or have property surveyed Coordinating volunteers and homeowner communication is a large job, best suited for a lead partner Experienced volunteers begin treating stiltgrass on private properties Stiltgrass signs at nearby parks, preserves Plan for boot brush installation Contractor treatment on private property

19 Management All-hands-on-deck effort completed by private landowners, volunteers, private contractors, WSWG partners. Several options are available for different budgets, land types, personal preference. o Mechanical options o Chemical options o Results from 2018 Information based on one year of treatment

20 Management Mechanical Hand Pulling Appropriate for: o High quality areas o Small infestations (area and density) o Limited resources and lots of time Ideal in late July-August, after plants are matured but before seed set Several follow-up visits Disposed of stiltgrass with waste (not compost)

21 Management Mechanical Propane Torching Spot-burning shortly before seed set Perennials should return following year Less time consuming than hand-pulling Early spring controlled burns may promote establishment and growth of stiltgrass vs propane spot burning after germination L. Flory, J. Lewis (2009)

22 Management Mechanical Mowing Weed whip Conduct in fall immediately before seed set o Conducting after seed production may promote spread No decline in native plant community More effective in sites recently invaded instead of established populations Decontamination of tools Luke Flory, Jason Lewis (2009). Nonchemical Methods for Managing Japanese Stiltgrass (Microstegium vimineum). Invasive Plant Science and Management, 2(4): Weed Science Society of America

23 Management Chemical Aquaneat, RoundUp (Glyphosate) Low active ingredients intended to control stiltgrass (annual) and not native perennials Different solutions: 0.25%, 0.5%, 1.0% WSWG partners discuss best treatment options

24 Management Chemical Glyphosate Aquaneat, Roundup 1.5 weeks after application of 0.25% 2% Glyphosate 2% Pelargonic Acid

25 Management Chemical Aquaneat, RoundUp (Glyphosate) Low active ingredients intended to control stiltgrass (annual) and not native perennials Different solutions: 0.25%, 0.5%, 1.0% Fusilade (Fluazifop-P-butyl) Grass-specific 0.5% solution Not to be used near water WSWG partners discuss best treatment options

26 Management Chemical Fusilade (Fluazifop-P-butyl) at 0.5% active ingredient 1.5 weeks after application

27 Management Chemical Aquaneat, RoundUp (Glyphosate) Low active ingredients intended to control stiltgrass (annual) and not native perennials Different solutions: 0.25%, 0.5%, 1.0% Fusilade (Fluazifop-P-butyl) Grass-specific 0.5% solution Not to be used near water WSWG partners discuss best treatment options Scythe (Pelargonic Acid) Quick Acting, not selective Best for treating annual weeds Breaks down quickly

28 Management Results Treated stiltgrass on 200 acres! Chemical treatment was effective where enough was applied Difficulty in finding all stiltgrass populations and applying enough herbicide to reach all layers of stiltgrass Pelargonic acid and glyphosate Torching is also effective, but much more time consuming than foliar spray Hand-pulling decreased the amount of stiltgrass, but it didn t eliminate it, and it was very time consuming With all methods, plan on follow-up visits We were not able to survey, treat all properties

29 Celebrate Success! Creation of Washtenaw Stiltgrass Working Group Successful outreach to 80+ neighbors Hosted 7 workshops to teach identification and treatment Surveyed hundreds of acres Professionals, volunteers, partners worked 450+ hours to manage stiltgrass $27,000 in grants, donations, and partner match secured for 2019 WSWG partners and stiltgrass warriors were invited to fall Celebration of Stewardship

30 Lessons Learned Expect to find more Starting treatment too early means you might miss several populations Data collection plan Can get tedious, know what you re signing up for Make a plan for fundraising early Getting funding can take time

31 Plans for 2019 o WSWG received funding through Jackson Lenawee Washtenaw CISMA and ITC for treatment o Hire coordinator o PR/Outreach o TSN o mparks o WAM o Local talks, workshops o Bring in new partners and landowners o Mapping o Treatment Pre-emergence Post-emergence

32 Resources to help MISIN Report Resources per state Check with your local CISMA If you re in Washtenaw County, Tap into local resources: Universities, watershed councils, Stewardship Network Clusters, land conservancies, municipalities, state natural resource departments, and more!

33 Questions? Becky Gajewski Katie Carlisle x334 Grab an ID guide! Washtenaw Stiltgrass Working Group