Restoration Project Proposal: Fresh Creek Nature Preserve

Brooklyn, NY

 

Lindsay Ries

 

                                                Photographed by Lindsay Ries, 11/20/06

 

ABSTRACT

 

A restoration project has been proposed for Fresh Creek Park Preserve.  This park is owned by the New York City Department of Parks and Recreation and provides an important buffer for the Jamaica Bay.  A combined sewage overflow, lack of fringing salt marsh habitats alongside the creek and invasive species threaten the Fresh Creek ecosystem and contribute to water quality issues and reductions in available habitat for wildlife.  Currently, the Jamaica Bay Ecosystem Restoration Project team is planning for a project in this location, but an outline of the plan has not been finalized.  This publication proposes a plan that includes 5 separate phases of construction, followed by a 5-year minimum for monitoring each phase.  These phases include leveling the sediment in the channel to increase tidal flow, removing structural barriers such as rocks and bulkheads to restore natural salt marshes, eradicating outlying populations of invasive species and creating an oyster reef near the mouth of the creek to improve water quality.  The estimated budget for this plan would be $80,000, and could fluctuate based on community involvement with volunteer projects during each of the phases.  Restoring tributaries of Jamaica Bay becomes extremely important due to the rapid losses of salt marsh islands during the past 100 years and with scientists estimating their total demise in less than 20 years if current rates of loss continue.    

 

BACKGROUND

 

The Fresh Creek Park Preserve is 92-acre natural salt marsh reserve, protected under the Forever Wild program with the New York City Department of Parks and Recreation (NYCDPR, 2006).  The creek is surrounded by residential homes to the west on 108^th Street, Flatlands Avenue directly to the north and Louisiana Avenue to the east (Fig 1).  Fresh Creek itself accounts for 42 acres, and is approximately 6,300 ft long, 125-650 ft wide, and flows south directly into the Jamaica Bay.  The depth of this tributary ranges from 3-19 ft, with the creek deepening as it approaches Jamaica Bay (NYCDEP, 2006).  Fresh Creek along with several other Jamaica Bay tributaries act as natural buffers that trap and filter pollutants from runoff and Combined Sewer Overflows (CSOs) that would otherwise enter the bay.  The Jamaica Bay Ecosystem Restoration Project (JABERP), led by the U.S Army Corp of Engineers, announced their intentions in February 2005 of restoring Fresh Creek, along with 7 other sites.  However, their plans have not been finalized and are currently not available to the public for review.  It is estimated that the total costs for all 8 of the Jamaica Bay sites in the project will be $75-100 million dollars (Jamaica Bay Task Force, 2005). 

 

Fresh Creek used to be a much smaller and shallower tidal creek (Jamaica Bay Task Force, 2005).  However, it was deeply dredged in the late 1800s/early 1900s due to development along the shore line, and people’s desire for access to the Jamaica Bay.  Bulkheads were and are still used today by shoreline residents of Fresh Creek.  They have contributed to the further deepening of the creek in certain sections by providing an abrupt edge and restricting the natural tidal flow.  Shellfishing, a way of life for oysterman living in and around Jamaica Bay, also ended in 1921 due to the sensitivity of oysters to the pollution generated from this major increase in population and development.  Tourists and new residents came in large numbers and ultimately caused large loads of raw untreated sewage to enter the bay, posing major health risks for humans and for wildlife (Baykeeper, 2006).  Shellfishing is currently still prohibited, although Jamaica Bay’s water quality has slightly improved due to the construction of sewage treatment plants (Steinberg et al, 2004). 

 

Restoration in and around Jamaica Bay has become essential for supporting the wide array of estuarine species that are dependent on the sheltered, salt marsh ecosystem.  Jamaica Bay, and parts of Fresh Creek, provide fish and shellfish nurseries for species such as Morone saxatilis (striped bass), Pleuronectes americanus (winter flounder), Paralichthyus dentatus (summer flounder), Morone americana (white perch), Anguilla rostrata (American eel), and 3 species of forage fish which provide food for larger fish and wading birds (Steinberg et al, 2004).  However, the survival of these fish and native crustaceans is directly dependent on the abundance of Spartina alterniflora (cordgrass), the plant species responsible for the productivity of salt marshes and their associated biodiversity on the Atlantic coast (Niedowski, 2000). 

 

The Jamaica Bay is in serious need of additional restoration, and ecologists and engineers of the JABERP face unique challenges concerning losses of sedimentation and rises in sea level (Roman, 2006).  Currently, salt marshes in the Jamaica Bay account for only 50% of the original islands that were observed in 1924.  If losses continue at their present rate of 44 acres per year, all salt marsh islands in the Jamaica Bay are estimated to disappear in less than 20 years (Steinberg et al, 2004).  With current reductions in salt marshes available for estuarine species, restoration of salt marshes in tributaries, such as Fresh Creek, will be essential in providing additional areas for refuge.   

 

 

CURRENT THREATS

 

The major threats to the Fresh Creek Park Preserve are pollutants entering the creek (and ultimately the Jamaica Bay), structural barriers and invasive species.  Jamaica Bay is included in New York State’s list of 18 water bodies surrounding the five boroughs of New York City (NYC) that are, “substantially “impaired” for human uses or aquatic life as a result of pathogens, oxygen demand, nitrogen or trash discharged in CSOs” (Riverkeeper, 2006).  A portion of this waste is from a Combined Sewage Overflow (CSO) system located at the head of Fresh Creek, along with storm sewer discharges along its length (NYCDEP, 2006).  It is one of NYCs largest, draining around 2170 acres and flow volumes ranging from 1-70 million galloons (MG) were documented during an EPA study in the mid-1990s (EPA, 1999). 

 

Overflows contain untreated sewage and polluted runoff, which is discharged directly into the creek.  The intensity and timing of overflow events depends on the amount of rainfall, but occurs once a week on average (Riverkeeper, 2006).  Although the daily tides cause water to move in and out of the entire system, Jamaica Bay suffers from high residence times.  One droplet of water stays in the Jamaica Bay for approximately 35 days, which is an extremely long time relative to other areas in the Hudson (Baykeeper, 2006).  This causes major water quality issues for the people and wildlife living in and around Fresh Creek and the Jamaica Bay.

 

Fortunately, the CSO at Fresh Creek has a Netting TrashTrap system that filters floatable debris.  In 1993 the nets were 90-95% efficient, and the nets were expanded further to cover the entire outfall to catch all floatable debris (EPA, 1999).  This debris would otherwise enter the Jamaica Bay, causing hazards for boaters, beachgoers, and wildlife through harmful ingestion or entanglement (Steinberg et al, 2004).  In addition, impermeable surfaces in highly urbanized areas such as Brooklyn allow large amounts of pollutant runoff to directly enter the water through storm sewers. 

 

The O’Brien & Gere Company has been involved in the CSO abatement plans in NYC for over 10 years, and has recommended a 34 MG CSO retention tank at Fresh Creek that would retain 70% of discharges to Fresh Creek.  The storage basins could than be pumped to the sewage treatment plant within 24 hours (O’Brien & Gere, 2005).  This would be highly desirable for the health of Fresh Creek and the Jamaica Bay, but the city has made no authorizations for construction of the project thus far.  Harmful algal blooms have also been a cause for concern in the region, with multiple incidences in Jamaica Bay.  A range of 31-60 harmful algal blooms occurred from 1975- 1995 in the Grassy Bay, just south of Fresh Creek.  Although the exact causes for harmful algal blooms are unknown, they are mostly correlated with areas with poor water quality.  Although reports have indicated improvements in Jamaica Bay’s water quality, there is still a lot more that needs to be done to ensure the safety of the wildlife and people living in the area (Steinberg et al, 2004).     

 

A mounting threat for native salt marsh species has been the colonization and establishment of invasive species.  One of the most threatening invasives, Phragmites australis (common reed), grows in degraded salt marshes and dominate sites due to their incredible reproductive capabilities.  Once established, they regularly outcompete native plants in the mid to upper marsh where salt conditions are lower and more favorable for this particular invasive.  Although the plant grows very densely and could be beneficial in buffering the creek (Antonio et al, 2002), common reed can be damaging to natural salt marshes because they alter plant species compositions and ecosystem functioning.  As mentioned earlier, cordgrass is essential in salt marsh ecosystems.  Their stems trap floating debris, and this decayed matter forms detritus which supports life on the marsh.  In addition, the death of cordgrass at the end of the season causes a spongy peat layer that raises the surface and allows other less salt tolerant species to colonize.  Common reed colonizes aggressively in these newly developed areas and their deep and expanding roots could cause a drying effect which would threaten populations of native salt marsh species (Niedowski, 2000).  Overall, Fresh Creek poses many challenges for restoration ecologists.

 

 

 

 

RESTORATION OBJECTIVES

 

For an ecological restoration project at Fresh Creek, anthropogenic effects such as CSO inputs need to be taken into consideration.  In addition, although the proposed restoration project will enhance the salt marsh habitat along Fresh Creek, a macroscopic perspective is needed to understand effects on the entire Jamaica Bay ecosystem.  The hydrology of the creek will also be directly affected by additional restoration efforts in the Jamaica Bay.  Thus, this project could be used in combination with current and future JABERP projects.

 

The restoration goal for Fresh Creek Park is to optimize the remaining salt marsh habitat, increase tidal inundation and improve water quality conditions in 5 separate phases.  Phase 5 will be contingent on current progress of oyster restoration in Jamaica Bay and the installation of the 30 MG retention tanks for the CSO at the head of Fresh Creek (O’Brien & Gere, 2005).  With the installation of retention tanks, oysters translocated in Phase 5 would filter less harmful pollutants such as bacteria, thus improving their health and susceptibility to diseases.  In addition, connectivity via larval transport to other oyster reefs throughout Jamaica Bay and the Hudson-Raritan Estuary would be needed to promote genetic diversity and overall resiliency of the reef (Baykeeper, 2006). 

 

Locations for each phase can be seen in Figure 1. 

 

• Phase 1: Level current sediment mounds to increase tidal flush

 

• Phase 2: Restore fringing salt marsh vegetation for erosion control

 

• Phase 3: Remove the structural barrier (bulkhead) to restore salt marsh.  

 

• Phase 4: Eradicate 2 patches of invasive common reed

 

• Phase 5: Oyster reef restoration 

 

 

Figure 1: Restoration objectives for Fresh Creek Nature Preserve.  Adapted map, original map available at: www.nyc.gov/parks

 

 

RESTORATION OUTLINE

 

The following is a more detailed outline of the proposed plan, with a project timeline of 5 years, not including additional years needed for monitoring.  A timeline for the project is provided by appropriate seasons for each phase that should be followed.  Spring of 2008 is provided as an ideal starting point for the project, although the amount of time taken in between each phase is dependent upon manpower, unforeseen events and whether conditions are met for the implementation of Phase 5.

 

Spring 2007

 

1. Seed Collection for Phase 2:  Seeds need to collected for seedlings that will be used in salt marsh restoration for Phase 2
1. Seeds will be collected on-site, since the areas in Phase 2 are relatively small and closer to the CSO.  Cordgrass established at Fresh Creek has most likely evolved higher tolerances towards the overflow. 
2. Off-site areas that are ecologically similar and also contain nearby CSOs could be used as well to promote genetic diversity and overall resiliency of the augmented population of cordgrass alongside Fresh Creek.

 

Spring 2008

 

1. Phase 1: Level current sediment mound to increase tidal flush into and throughout Fresh Creek (Fig 1)

 

1. Could use a boat with bed leveler attached.  Bed leveler is usually a bar or blade that is pulled over the mound to level the sediment on the bottom.
2. No removal of sediment from the site, only leveling to increase tidal flush.
3. In the future, if sediment mound continues to build, may need to consider filling and leveling the entire creek.  Historically, the area just north of the mouth of Fresh Creek had been deeply dredged and bulkheads along the western side promote this continual deepening relative to the much shallower depths throughout the rest of the channel (McClain, personal communication).

 

2. Phase 2: Remove structural barriers (rocks) alongside the creek (Fig 1), restore slope and native salt marsh plant species for a natural vegetative barrier. 

 

1. Equipment (bulldozer) would be needed to remove most of the rocks from the area.  Fill may be needed to establish the desired slope, 1-3% (Niedowski, 2000).
2. Once the slopes have been stabilized for each area, native cordgrass seedlings would be added to the lower marsh zone. 

                                                               i.      Seeds were collected in the spring of 2007 and sent to a greenhouse to be propagated and raised. 

                                                             ii.      Seedlings planted in this phase would be seeds that were collected on-site and in ecologically similar sites.

                                                            iii.      Plant seedlings in 1 square foot plots: recommended for NYS (Niedowski, 2000).  Increases in plant density allow for greater stabilization of the shoreline.

3. Total area for 2A and 2B= 2,230 square ft

 

3. Seed Collection for Phase 3: Seeds need to be collected for seedlings that will be used in salt marsh restoration for Phase 3.
1. Seeds will be collected on-site and in ecologically similar areas to promote genetic diversity of the population of cordgrass at Fresh Creek. 
2. Sent to a local greenhouse to be propagated and raised for salt marsh restoration the following year.

 

 

 

 

Spring 2009

 

4. Phase 3:  Remove bulkhead, restore slope and salt marsh for vegetative erosion control and habitat

 

1. Larger equipment will be needed to remove bulkhead
2. Fill may be needed to restore the slope to 1-3% (Niedowski, 2000)

                                                               i.      A gentle slope provides topographic heterogeneity to the shoreline, allowing for different salt marsh zones and increases in biodiversity (Falk et al, 2006).

3. Plant native cordgrass seedlings

                                                               i.      Seeds were collected in the spring of 2008.

4. Although invasive common reed is plentiful in this area, tidal inundation due to the restoration of the salt marsh in this area will act as the control method (Niedowski, 2000).

                                                               i.      Would want to avoid large-scale eradication efforts during this project.  However, the area should be monitored and common reed may need to be eradicated in this area if the invasive continues to dominate this section of Fresh Creek. 

                                                             ii.      Salt provides a natural ecophysiological constraint for common reed but cordgrass has evolved in the natural lower zones of salt marsh ecosystems and is able to thrive with tidal inundation of salt water (Falk et al; Niedowski, 2000). 

5. Total area= 10,000 square ft
6. Phase 2A, 2B, and 3 would require approximately 9,000 potted seedlings

 

                                               Fall 2010

 

5. Phase 4: Eradicate 2 patches of invasive common reed

 

1. 2 relatively small patches (~150 square ft) identified in lower salt marsh zone (Fig 1).

                                                               i.      Targeting small and outlying populations such as these 2 small patches at Fresh Creek would be an effective way to slow landscape-scale invasion rates once an invader such as common reed is established (Falk et al, 2006). 

                                                             ii.      Large-scale disturbances in the uplands were undesired and may cause increases in the amount and diversity of invasives that re-colonize the area (Falk et al, 2006).

                                                            iii.      Monitoring the dispersal of common reed throughout Fresh Creek would be essential and preventive measures would need to be taken if it were to spread to areas with no invasives present.

2. Control method: Herbicidal cut-stem treatment.
3. Herbicide: EPA approved Rodeo (glyphosphate), followed by cutting and removal of biomass after several weeks (Tu, 2000)

 

 

Late Spring/Early Summer 2011

 

6. Phase 5: Oyster reef restoration

 

1. Restore Crassotrea virginica (Eastern oyster) populations
2. Method: Spat on a shell (Grizzle, 2006)
3. Cultch: oyster shells, would provide harder substrate

                                                               i.      Start a Shellfish Recycling program, to save costs on purchasing oyster shells.  Would involve asking for local shells from people and restaurants (Grizzle, 2006).

4. Use mostly hatchery larvae, can also add individuals raised in oyster gardens in Jamaica Bay

                                                               i.      Larvae from hatcheries may provide Jamaica Bay with healthier populations of oysters.  The larvae used in the project would be from oysters in the Long Island area. 

                                                             ii.      Native Jamaica Bay oysters in different parts of the bay could be translocated to the reef to increase the genetic diversity and overall resilience of the oyster reef.

5. This phase would be dependent on current oyster restoration progress in NYC and the addition of retention tanks to the CSO system.  The total area and amount of spat added to the oyster reef may not be enough to sustain the population.  Connectivity to other oyster populations, to allow for larval dispersal via water currents and tidal influences would be highly desirable and would be needed due to the small total area of the oyster reef that would be restored.  This would create a metapopulation of eastern oysters, leading to greater genetic diversity through abilities of dispersal and higher probabilities of overall resiliency of oyster populations (Falk et al, 2006).
6. Total area= 0.10 acre of shells (Fig 1)

 

The project would have a Before-After-Control-Impact design throughout all 5 phases for water quality, and a Before-After design for salt marsh restoration and the eradication of common reed (Falk et al, 2006).  The Control Site for water quality data would be Hendrix Creek, a tributary located directly east of Fresh Creek.  Multiple samples would be taken just north of the mouth of each creek before and after each phase.  Levels of dissolved oxygen, chlorophyll A, nitrogen, phosphorus and coliform bacteria would be tested to assess the effectiveness of the restored salt marshes and oyster reef in trapping and filtering pollutants.  Having Before-After-Control-Impact and Before-After designs in projects are essential in providing restoration ecologists with an experimental design.  If measurements are taken in this way, statistical analyses can be used to analyze the effectiveness of the set goals for the project.  In addition, topographic models based on sediment and tidal flow measurements into Fresh Creek would be extremely important in predicting future tidal inundations and deciding on future restoration projects in the Jamaica Bay.

 

The National Oceanic and Atmospheric Administration (NOAA) suggest 5 years of monitoring after restoring salt marshes and eradicating invasive species, which will be considered in the timeline of the project in the budget section.  Measurements relative to the survival and growth of planted cordgrass seedlings such as stem density, plant height, overall abundance and several other factors would be included in monitoring.  Protocol and monitoring forms can be used from NOAA’s Salt Marsh Restoring and Monitoring Guidelines report (Niedowski, 2000). 

 

BENEFITS OF PROPOSED PLAN

 

The proposed restoration project for Fresh Creek provides many benefits for the wildlife of Jamaica Bay, as well as for the people living in and around the tributary.  The creek has been altered from its natural form and residential homes in the area and the CSO system restrict the restoration of the tributary back to its original shape and size (Fig 1).  However, the proposed plan would optimize the salt marsh alongside the creek and restore degraded areas in the park.  The methods and ways in which the restoration plan would be implemented at Fresh Creek provide benefits of their own, relating to improving functionality and overall resiliency of the ecosystem.  The benefits of project are numerous, but include improvements in water quality, increases in habitat for estuarine species and community involvement.

 

Water quality has been a major issue for Jamaica Bay since it is relatively sheltered, causing lower amounts of tidal flush throughout the system.  As mentioned before, one droplet of water stays in the Jamaica Bay for approximately 35 days (Baykeeper, 2006).  Salt marshes and oysters could filter excess pollutants and runoff that enters the creek and ultimately the Jamaica Bay.  In addition, the small areas of salt marsh that would be restored in phases 2A and 2B are directly connected and adjacent to existing cordgrass patches.  This increases the area of the patch, allowing for greater amounts of colonization to the patch by other estuarine organisms and lower extinction risks (Falk et al, 2006).  In addition, the augmented cordgrass in phases 2 and 3 of the project would have a fairly connected metapopulation with other individual populations of cordgrass located in different sections of Jamaica Bay, Long Island, and Sandy Hook, NJ through dispersals via wind or water currents.         

 

 

ESTIMATED BUDGET

 

The budget for the project is an estimate based on past restoration projects, and could be adjusted based on the amount of volunteers gathered to assist in phases of the plan and the dependent implementation of Phase 5 (Table 1).

 

 

 

 

 

 

Phase Number	Items needed	Ways to reduce costs	Known costs
1	Bed leveling equipment
2	-Equipment to remove rocks -cordgrass seedlings -erosion control cover	Volunteers
3	-Equipment to remove bulkhead -fill for slope -cordgrass seedlings -erosion control cover	Volunteers	-Total area (Phase 2,3)= 0.65 acres -Total # seedlings= 9,000= $7,000 (Niedowski, 2000) -Salt marsh restoration = ~$50,000
4	Herbicide and applicators Mower	Volunteers
5	-Oyster shells -Oyster larvae -Container bins for larvae -mesh bags for shells -barge -powerwasher	-Shell recycling program -volunteer oyster gardeners -different cultch material that is less expensive than oyster shells	-Total area= 0.10 acres -Total costs for oyster restoration (seed, equipment, labor)= ~$5,000
		TOTAL ESTIMATED COST (+ costs for 5 years of monitoring after each phase)	$80,000

Table 1: Estimated budget for the Fresh Creek proposed restoration project.  The total salt marsh restoration was calculated by looking at costs per seedling and comparing the budget from a 4-acre salt marsh restoration project in Pelham Bay (NYCDPR, Dec 2006).  Oyster restoration costs were estimated based on a general conversion of costs based on acreage (FAO, 2004).  The additional $25,000 was added for additional work time needed for monitoring and adaptive management.

 

 

The total budget for the project would be ~$80,000, and could fluctuate depending on several factors mentioned previously.  Community involvement would not only reduce costs, but also increase awareness and provide educational opportunities.  The Fresh Creek Park Preserve is relatively off limits due to its coverage in the Forever Wild Program, although overlooks into the salt marsh can be accessed from the eastern side of the creek on Louisiana Avenue.  Allowing NYC residents to be a part of the project would allow them to be more connected with this park and their more natural surroundings. 

 

 

 

 

 

     

 

 

 

 

 

 

 

References

 

Antonio, C. et al. (2002). Exotic Plant Species as Problem and Solutions in Ecological

Restoration: A Synthesis. Restoration Ecology 10 (4): 703-713.

 

Baykeeper. NY/NJBaykeeper oyster restoration rationale and strategic plan for the

Hudson-Raritan Estuary. Nov 26, 2006

            < http://www.nynjbaykeeper.org/pdffiles/bkoppdoc.pdf>

 

Environmental Protection Agency. (1999). Combined Sewer Overflow Technology Fact

Sheet: Netting Systems for Floatable Control.

 

Falk, D. et al. (2006). Foundations of Restoration Ecology. Society for Ecological

Restoration International.

 

FAO Inland Water Resources and Aquaculture Service (FIRI). (2004). Cultured Aquatic

Species Information Programme- Crassostrea virginica. Cultured Aquatic Species Fact Sheets. Nov 11, 2006. <http://www.fao.org/figis/servlet/static?dom=culturespecies&xml=Crassostrea_virginica.xml>

 

Grizzle, R. Oyster Reef Restoration in the Mid-Atlantic States- Shellfish Recycling

Program. Oyster Restoration Program- Jackson Estuarine Laboratory, University of New Hampshire. Nov 26, 2006

< http://www.oyster.unh.edu/other%20restoration.html>

 

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Nov 26, 2006.

< http://nbii-nin.ciesin.columbia.edu/jamaicabay/jbtf/jbtf_minutes_021605.pdf>

 

McClain, Bobbi Jo. (2006). Personal Communication via email, Dec 1, 2006. 

 

New York City Department of Environmental Protection's (DEP) Use and Standards

Attainment Project.  Fresh Creek Tributary.  Oct 1, 2006.

<http://www.hydroqual.com/projects/usa/coneyIslandFrameset.html>

 

New York City Department of Parks and Recreation. Forever Wild- Fresh Creek Park

Preserve. Oct 1, 2006. <http://nycgovparks.org/sub_about/parks_divisions/nrg/forever_wild/site.php?FWID=22>

 

New York City Department of Parks and Recreation. Bronx Restoration Sites-

Pelham Lagoon- Salt Marsh Restoration. Dec 1, 2006.

<http://www.nycgovparks.org/sub_about/parks_divisions/nrg/nrg_rest_prior.html         

 

 

Niedowski, Nancy. (2000). New York State Salt Marsh Restoration and Monitoring

Guidelines. National Oceanic and Atmospheric Administration, prepared for the

New York State Department of State & New York State Department of Environmental Conservation.

 

O’Brien & Gere Company. (2005). Wet Weather Programs- Project Portfolio.

            Nov 21, 2006.

< http://www.obg.com/solutions/water/wet_projects.aspx>

 

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            < http://riverkeeper.org/campaign.php/pollution/we_are_doing/986>

 

Roman, C. (2006). Salt Marsh Loss: Possible Causes, Restoration Needs, and Research

Opportunities.  Jamaica Bay Research and Mangement Information Network, Advisory Committee Meeting Presentation. Nov 20, 2006.

< http://nbii-nin.ciesin.columbia.edu/jamaicabay/jbwppac/jbac_meetings.html>

 

Steinberg, N. et al. (2004). Health of the Harbor: The First Comprehensive Look at the

State of the NY/NJ Harbor Estuary. Hudson River Foundation.

 

Tu, M. (2000). Techniques from TNC Stewards for the eradication of Lythrum salicaria

(purple loosestrife) and Phragmites australis (common reed/Phrag) in wetlands. The Nature Conservancy: 1-13.