Proceedings of the Third International Conference on Invasive ...

Chapter 4: Spartina Control and Management<strong>Proceedings</strong> <strong>of</strong> <strong>the</strong> <strong>Third</strong> <strong>International</strong> <strong>Conference</strong> on Invasive SpartinaGel image <strong>of</strong> S. anglica (first 2 lanes) and S. alterniflora x foli hybridsBand is absent in S. alt (and S. foli)S. maritima band in S. anglicaFig. 2. Spartina anglica on Roberts Bank in August 2003.programs. Ducks Unlimited Canada and <strong>the</strong> Corporation <strong>of</strong>Delta issued several press releases. Delta established a website on Spartina anglica as part <strong>of</strong> <strong>the</strong>ir outreach program.An oral presentation describing <strong>the</strong> Fraser Spartina Bustersprogram was also made at <strong>the</strong> 3 rd <strong>International</strong> InvasiveSpartina <strong>Conference</strong> in San Francisco, November 8-10,2004.Volunteer Recruitment and ManagementVolunteer organizations and individuals were contactedby email providing information on <strong>the</strong> meeting time andplace, as well as mapping and field needs for <strong>the</strong> BoundaryBay S. anglica removal. A meeting room at <strong>the</strong> Delta AirPark was made available to <strong>the</strong> organizers for volunteer signup, supply and equipment staging, and brief orientation.Laminated S. anglica identification cards were given to allvolunteers to assist in accurate identification duringremovals.Several volunteer removal efforts were held from Juneand October in Boundary Bay and Roberts Bank. Eightyeightvolunteers participated in <strong>the</strong> June 17–19 removal. Afall follow-up was held October 13–15 supported by 19volunteers.Volunteers received a brief instruction on manualremoval methods in <strong>the</strong> meeting room during <strong>the</strong> Juneremoval, with field demonstrations conducted in subsequentremovals.Manual and Mechanical Removal MethodsThe manual removal methods were similar to <strong>the</strong>Roberts Bank program. However, an all-terrain vehicle,provided by Delta, was used to collect and transport bags to<strong>the</strong> dike. Filled bags were piled at collection points on top <strong>of</strong><strong>the</strong> dike and subsequently loaded by backhoe into a truckFig. 3. DNA analysis gel image <strong>of</strong> Roberts Bank S. anglica (left samples)showing S. maritima bands and absence <strong>of</strong> S. alterniflora (courtesy <strong>of</strong> D.Ayres, University <strong>of</strong> California, Davis).and taken to <strong>the</strong> GVRD incinerator, where <strong>the</strong>y wereweighed prior to incineration.For larger clones (i.e., >1 m diameter), an amphibiousswamp excavator operated by Concord Excavating andContracting Ltd. was used to bury <strong>the</strong> plants in deep holesexcavated in <strong>the</strong> mudflat. The machine ran on large trackedpontoons and left a light footprint on <strong>the</strong> ground (< 1 psi).Excavated S. anglica was buried in holes about 3–5 m deepand backfilled with excavated material, which was graded to<strong>the</strong> surrounding substrate (referred to earlier as in situburial). At some locations, GPS was used to record <strong>the</strong>location for future monitoring. The excavator was also usedto remove several large clones in <strong>the</strong> western section <strong>of</strong>Boundary Bay in June.Two removal efforts were also conducted at <strong>the</strong> RobertsBank site. On August 5, <strong>the</strong> swamp excavator was used tocomplete in situ burial <strong>of</strong> <strong>the</strong> three large clones. A volunteerremoval <strong>of</strong> seedings occurred on September 28, involvingeight person-days <strong>of</strong> effort.RESULTSSpartina IdentificationS. anglica was quite easily identified based on habitatand plant characteristics. Most plants colonized mudflatelevations well below native salt marsh. The oblique bladeand vertical spikelet arrrangements were distinguishingcharacteristics in <strong>the</strong> field (Fig. 2).DNA analysis showed <strong>the</strong> distinctive S. maritima bands,lacking in S. alterniflora (Fig. 3). However, due to <strong>the</strong>limited genetic variation in S. anglica, it was not possible todetermine <strong>the</strong> source <strong>of</strong> <strong>the</strong> Fraser River estuary specimens(D. Ayres, pers. comm.).- 238 -