Search

Search Results

• 1. [Article] Aquatic Invasive Species Surveys of Upper Klamath Lake, Fourmile Lake, and Lake of the Woods, OR During 2012

  Three lakes located within the Klamath River Basin in Oregon (Upper Klamath Lake, Fourmile Lake, and Lake of the Woods) were surveyed for aquatic invasive species during the summer of 2012. Specimens were ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Invasive Species Surveys of Upper Klamath Lake, Fourmile Lake, and Lake of the Woods, OR During 2012 Author: Miller, Rich, Sytsma, Mark D. Year: 2013 Three lakes located within the Klamath River Basin in Oregon (Upper Klamath Lake, Fourmile Lake, and Lake of the Woods) were surveyed for aquatic invasive species during the summer of 2012. Specimens were collected using plant rakes, benthic dredges, plankton nets, and crayfish traps. No invasive aquatic plants, gastropods, snails, bivalves or crayfish were detected in the lakes. Title: Aquatic Invasive Species Surveys of Upper Klamath Lake, Fourmile Lake, and Lake of the Woods, OR During 2012 Author: Miller, Rich, Sytsma, Mark D. Year: 2013 Three lakes located within the Klamath River Basin in Oregon (Upper Klamath Lake, Fourmile Lake, and Lake of the Woods) were surveyed for aquatic invasive species during the summer of 2012. Specimens were collected using plant rakes, benthic dredges, plankton nets, and crayfish traps. No invasive aquatic plants, gastropods, snails, bivalves or crayfish were detected in the lakes. Close

• 2. [Article] Survey of Aquatic Invasive Species in Selected Umpqua National Forest Lakes and Ponds

  Eleven lakes and ponds within the Umpqua National Forest were surveyed for invasive aquatic macrophytes, snails, bivalves, and crayfish during the summer of 2011. Yellow floating heart (Nymphoides peltata), ...

  Citation × Citation Citation Abstract Copy Title: Survey of Aquatic Invasive Species in Selected Umpqua National Forest Lakes and Ponds Author: Sytsma, Mark D., Miller, Rich Year: 2012 Eleven lakes and ponds within the Umpqua National Forest were surveyed for invasive aquatic macrophytes, snails, bivalves, and crayfish during the summer of 2011. Yellow floating heart (Nymphoides peltata), an invasive floating leaf macrophyte species, was detected in Willow Sump within the Little River drainage. European ear snails (Radix auricularia), an invasive species present in several Umpqua National Forest waterbodies, were detected in Beaver Pond within the Steamboat Creek drainage. One native crayfish species, the signal crayfish (Pacifastacus leniusculus), was observed in Crayfish Lake within the Brice Creek drainage. Diverse assemblages of native plant species were observed in the lakes and ponds. The UNF and the Oregon Department of Agriculture are exploring ways to eradicate the yellow floating heart infestation in Willow Sump. Title: Survey of Aquatic Invasive Species in Selected Umpqua National Forest Lakes and Ponds Author: Sytsma, Mark D., Miller, Rich Year: 2012 Eleven lakes and ponds within the Umpqua National Forest were surveyed for invasive aquatic macrophytes, snails, bivalves, and crayfish during the summer of 2011. Yellow floating heart (Nymphoides peltata), an invasive floating leaf macrophyte species, was detected in Willow Sump within the Little River drainage. European ear snails (Radix auricularia), an invasive species present in several Umpqua National Forest waterbodies, were detected in Beaver Pond within the Steamboat Creek drainage. One native crayfish species, the signal crayfish (Pacifastacus leniusculus), was observed in Crayfish Lake within the Brice Creek drainage. Diverse assemblages of native plant species were observed in the lakes and ponds. The UNF and the Oregon Department of Agriculture are exploring ways to eradicate the yellow floating heart infestation in Willow Sump. Close

• 3. [Article] Aquatic Invasive Species Surveys of Pacificorp’s North Umpqua River Impoundments

  Ten North Umpqua Hydroelectric Project impoundments were surveyed for aquatic invasive species during the summer of 2012. One non-native submersed aquatic vegetation species (Potamogeton crispus) and one ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Invasive Species Surveys of Pacificorp’s North Umpqua River Impoundments Author: Miller, Rich, Sytsma, Mark D., Morgan, Vanessa Howard Year: 2013 Ten North Umpqua Hydroelectric Project impoundments were surveyed for aquatic invasive species during the summer of 2012. One non-native submersed aquatic vegetation species (Potamogeton crispus) and one non-native snail species (Radix auricularia) was detected. No crayfish or mussel veligers were collected and no non-native zooplankton species were encountered. Title: Aquatic Invasive Species Surveys of Pacificorp’s North Umpqua River Impoundments Author: Miller, Rich, Sytsma, Mark D., Morgan, Vanessa Howard Year: 2013 Ten North Umpqua Hydroelectric Project impoundments were surveyed for aquatic invasive species during the summer of 2012. One non-native submersed aquatic vegetation species (Potamogeton crispus) and one non-native snail species (Radix auricularia) was detected. No crayfish or mussel veligers were collected and no non-native zooplankton species were encountered. Close

• 4. [Article] Oregon Lake Watch, 2014 Annual Report

  The Oregon Lake Watch (OLW) volunteer monitoring program is now in its second year of operation, continuing its focus on early detection of aquatic invasive species (AIS), with a secondary focus on lake ...

  Citation × Citation Citation Abstract Copy Title: Oregon Lake Watch, 2014 Annual Report Author: Jordan, Meredith, Miller, Rich, Strecker, Angela L. Year: 2015 The Oregon Lake Watch (OLW) volunteer monitoring program is now in its second year of operation, continuing its focus on early detection of aquatic invasive species (AIS), with a secondary focus on lake water quality. The aquatic invasive species chosen as Watch List priorities for the OLW are based on the Oregon Department of Agriculture’s Noxious Weed List (Oregon Department of Agriculture Noxious Weed Control Program 2014) as well as professional judgement (more information can be found in Oregon Lake Watch Final Report 2014). This report summarizes the data collected by 15 of 24 OLW volunteers over 2014, across 110 sampling events and 20 Oregon lakes. Data collected by trained volunteers includes sightings of both native and aquatic invasive plants and animals, as well as recordings of lake temperature profiles, and Secchi depth, a measure of clarity. Of the 16 original water bodies surveyed in OLW’s first year (2013), 12 were surveyed again in 2014, and 8 are new waterbodies. Long-term monitoring of these lakes provides valuable information over time, and expanding the number of lakes monitored, especially in the case of monitoring for invasive species, means that more potentially harmful invasions can be stopped sooner. Ideally, the OLW will continue to monitor these current lakes, and expand their volunteer network to cover more waterbodies across Oregon as this program continues to grow. Title: Oregon Lake Watch, 2014 Annual Report Author: Jordan, Meredith, Miller, Rich, Strecker, Angela L. Year: 2015 The Oregon Lake Watch (OLW) volunteer monitoring program is now in its second year of operation, continuing its focus on early detection of aquatic invasive species (AIS), with a secondary focus on lake water quality. The aquatic invasive species chosen as Watch List priorities for the OLW are based on the Oregon Department of Agriculture’s Noxious Weed List (Oregon Department of Agriculture Noxious Weed Control Program 2014) as well as professional judgement (more information can be found in Oregon Lake Watch Final Report 2014). This report summarizes the data collected by 15 of 24 OLW volunteers over 2014, across 110 sampling events and 20 Oregon lakes. Data collected by trained volunteers includes sightings of both native and aquatic invasive plants and animals, as well as recordings of lake temperature profiles, and Secchi depth, a measure of clarity. Of the 16 original water bodies surveyed in OLW’s first year (2013), 12 were surveyed again in 2014, and 8 are new waterbodies. Long-term monitoring of these lakes provides valuable information over time, and expanding the number of lakes monitored, especially in the case of monitoring for invasive species, means that more potentially harmful invasions can be stopped sooner. Ideally, the OLW will continue to monitor these current lakes, and expand their volunteer network to cover more waterbodies across Oregon as this program continues to grow. Close

• 5. [Article] Aquatic Invasive Species Surveys of Eastern Oregon Waterbodies in 2013 and 2014

  Early detection aquatic invasive species (AIS) surveys were conducted at 33 Eastern Oregon waterbodies during the summers of 2013 and 2014. Submerged aquatic plants, gastropods, bivalves, and crayfish ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Invasive Species Surveys of Eastern Oregon Waterbodies in 2013 and 2014 Author: Miller, Rich, Sytsma, Mark D. Year: 2014 Early detection aquatic invasive species (AIS) surveys were conducted at 33 Eastern Oregon waterbodies during the summers of 2013 and 2014. Submerged aquatic plants, gastropods, bivalves, and crayfish were collected using a thatch rake, benthic dredge, plankton net, and modified minnow traps. Shoreline aquatic noxious weeds were noted when present and water quality characteristics were measured. Two AIS snail species, one AIS crayfish species, and five AIS plant species were detected during the surveys. Big-ear radix snails (Radix auricularia) were newly detected at 14 waterbodies distributed across the survey area. Chinese mystery snails (Cipangopaludina chinensis) were detected in one waterbody. Rusty crayfish (Orconectes rusticus) were newly found at high densities at one lake. AIS plant species included Eurasian watermilfoil (Myriophyllum spicatum), a hybrid of Eurasian with the native northern watermilfoil (M. spicatum x sibiricum), curlyleaf pondweed (Potamogeton crispus), fragrant waterlily (Nymphaea odorata) and reed canarygrass (Phalaris arundinacea). Fifty-six native aquatic plant species were identified in the waterbodies. Water quality conditions ranged from clear, low ionic strength water to highly turbid, productive, high ionic strength water. Title: Aquatic Invasive Species Surveys of Eastern Oregon Waterbodies in 2013 and 2014 Author: Miller, Rich, Sytsma, Mark D. Year: 2014 Early detection aquatic invasive species (AIS) surveys were conducted at 33 Eastern Oregon waterbodies during the summers of 2013 and 2014. Submerged aquatic plants, gastropods, bivalves, and crayfish were collected using a thatch rake, benthic dredge, plankton net, and modified minnow traps. Shoreline aquatic noxious weeds were noted when present and water quality characteristics were measured. Two AIS snail species, one AIS crayfish species, and five AIS plant species were detected during the surveys. Big-ear radix snails (Radix auricularia) were newly detected at 14 waterbodies distributed across the survey area. Chinese mystery snails (Cipangopaludina chinensis) were detected in one waterbody. Rusty crayfish (Orconectes rusticus) were newly found at high densities at one lake. AIS plant species included Eurasian watermilfoil (Myriophyllum spicatum), a hybrid of Eurasian with the native northern watermilfoil (M. spicatum x sibiricum), curlyleaf pondweed (Potamogeton crispus), fragrant waterlily (Nymphaea odorata) and reed canarygrass (Phalaris arundinacea). Fifty-six native aquatic plant species were identified in the waterbodies. Water quality conditions ranged from clear, low ionic strength water to highly turbid, productive, high ionic strength water. Close

• 6. [Article] OSMB Final Report, Task 7: Online Atlas of Oregon Lakes - Aquatic Invasive Species Interface

  In order to educate a broad cross section of the public about Aquatic Invasive Species (AIS) distributions and survey efforts in Oregon’s lakes and reservoirs, database connections were created to display ...

  Citation × Citation Citation Abstract Copy Title: OSMB Final Report, Task 7: Online Atlas of Oregon Lakes - Aquatic Invasive Species Interface Author: Miller, Rich, Sytsma, Mark D. Year: 2014 In order to educate a broad cross section of the public about Aquatic Invasive Species (AIS) distributions and survey efforts in Oregon’s lakes and reservoirs, database connections were created to display AIS information on the Online Atlas of Oregon Lakes (aol.research.pdx.edu/). The connections allowed for the dynamic display of AIS survey records stored in three separate databases: the Center for Lakes and Reservoir’s Oregon Aquatic Plant and Mussel Databases and the iMapInvasives database. AIS survey records collected by the Center for Lakes and Reservoirs were also reported to the iMapInvasives database. Title: OSMB Final Report, Task 7: Online Atlas of Oregon Lakes - Aquatic Invasive Species Interface Author: Miller, Rich, Sytsma, Mark D. Year: 2014 In order to educate a broad cross section of the public about Aquatic Invasive Species (AIS) distributions and survey efforts in Oregon’s lakes and reservoirs, database connections were created to display AIS information on the Online Atlas of Oregon Lakes (aol.research.pdx.edu/). The connections allowed for the dynamic display of AIS survey records stored in three separate databases: the Center for Lakes and Reservoir’s Oregon Aquatic Plant and Mussel Databases and the iMapInvasives database. AIS survey records collected by the Center for Lakes and Reservoirs were also reported to the iMapInvasives database. Close

• 7. [Article] OSMB Final Report, Task 4: Oregon Lake Watch

  The Oregon Lake Watch (OLW) volunteer monitoring program was resurrected after over a decade in hibernation. The new program was designed to educate the public about threats of aquatic invasive species ...

  Citation × Citation Citation Abstract Copy Title: OSMB Final Report, Task 4: Oregon Lake Watch Author: Strecker, Angela L., Miller, Rich, Morgan, Vanessa Year: 2014 The Oregon Lake Watch (OLW) volunteer monitoring program was resurrected after over a decade in hibernation. The new program was designed to educate the public about threats of aquatic invasive species (AIS), provide early detection of AIS invasions, and provide long term water quality data for the better management of Oregon’s lakes and reservoirs. Protocols were created for citizen scientists to survey for AIS, collect temperature and water clarity data, and record the data through an online data entry portal. An OLW website was developed to educate about AIS and provide survey protocols and identification materials to volunteers. AIS surveys were focused on Watch List Species which are selected AIS that have a negative impact on the beneficial uses of our waterbodies. Eighteen volunteers were trained during five sessions conducted in western and central Oregon. Fourteen of the trained volunteers collected data from sixteen waterbodies. Six Watch List species and one other AIS species were observed in four of the waterbodies. The three Watch List Species observed in Salish Pond and one in Olallie Lake were new observations. Temperature measurements indicated a wide range of thermal profiles and Secchi transparency measurement indicated a range of trophic status from oligotrophic to eutrophic. Title: OSMB Final Report, Task 4: Oregon Lake Watch Author: Strecker, Angela L., Miller, Rich, Morgan, Vanessa Year: 2014 The Oregon Lake Watch (OLW) volunteer monitoring program was resurrected after over a decade in hibernation. The new program was designed to educate the public about threats of aquatic invasive species (AIS), provide early detection of AIS invasions, and provide long term water quality data for the better management of Oregon’s lakes and reservoirs. Protocols were created for citizen scientists to survey for AIS, collect temperature and water clarity data, and record the data through an online data entry portal. An OLW website was developed to educate about AIS and provide survey protocols and identification materials to volunteers. AIS surveys were focused on Watch List Species which are selected AIS that have a negative impact on the beneficial uses of our waterbodies. Eighteen volunteers were trained during five sessions conducted in western and central Oregon. Fourteen of the trained volunteers collected data from sixteen waterbodies. Six Watch List species and one other AIS species were observed in four of the waterbodies. The three Watch List Species observed in Salish Pond and one in Olallie Lake were new observations. Temperature measurements indicated a wide range of thermal profiles and Secchi transparency measurement indicated a range of trophic status from oligotrophic to eutrophic. Close

• 8. [Article] Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011

  The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011 Author: Sytsma, Mark D., Miller, Rich, Morgan, Vanessa Year: 2011 The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. Early detection of new invasions can improve chances for successful eradication or containment to reduce the risk of IAPS spread. The Oregon Department of Agriculture (ODA) lists the most egregious offenders as “Noxious Weeds” which are defined as plants classified by the Oregon State Weed Board that are injurious to public health, agriculture, recreation, wildlife, or any public or private property (ODA 2011). Several IAPS classified as noxious have been detected within the Medford District of the Bureau of Land Management (BLM) in Southern Oregon including yellow floating heart (Nymphoides peltata) and yellow flag iris (Iris pseudacorus). During the summers of 2010 and 2011, IAPS surveys were conducted at selected reservoirs, lakes, and river boat launches within the Medford District to determine the extent of IAPS infestations as well as the distributions of native aquatic plant species. This report summarizes results of the surveys and provides recommendations for management of IAPS within the Medford District. Observations of any invasive aquatic animal species such as New Zealand mudsnails (Potamopyrgus antipodarum) are also reported. Title: Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011 Author: Sytsma, Mark D., Miller, Rich, Morgan, Vanessa Year: 2011 The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. Early detection of new invasions can improve chances for successful eradication or containment to reduce the risk of IAPS spread. The Oregon Department of Agriculture (ODA) lists the most egregious offenders as “Noxious Weeds” which are defined as plants classified by the Oregon State Weed Board that are injurious to public health, agriculture, recreation, wildlife, or any public or private property (ODA 2011). Several IAPS classified as noxious have been detected within the Medford District of the Bureau of Land Management (BLM) in Southern Oregon including yellow floating heart (Nymphoides peltata) and yellow flag iris (Iris pseudacorus). During the summers of 2010 and 2011, IAPS surveys were conducted at selected reservoirs, lakes, and river boat launches within the Medford District to determine the extent of IAPS infestations as well as the distributions of native aquatic plant species. This report summarizes results of the surveys and provides recommendations for management of IAPS within the Medford District. Observations of any invasive aquatic animal species such as New Zealand mudsnails (Potamopyrgus antipodarum) are also reported. Close

• 9. [Article] 2014 Aquatic Weed Surveys in Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake

  The Clackamas River Hydroelectric Project No. 2195 (Project) is located on the Oak Grove Fork of the Clackamas River and the mainstem of the Clackamas River in Clackamas County, Oregon. Reservoirs included ...

  Citation × Citation Citation Abstract Copy Title: 2014 Aquatic Weed Surveys in Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake Author: Miller, Rich, Sytsma, Mark D., Brittain, Jeffrey Thomas Year: 2014 The Clackamas River Hydroelectric Project No. 2195 (Project) is located on the Oak Grove Fork of the Clackamas River and the mainstem of the Clackamas River in Clackamas County, Oregon. Reservoirs included in the Project include Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake. The operator of the Project, Portland General Electric (PGE), was issued a license on December 21, 2010 by the Federal Energy Regulatory Commission (FERC) for continued operations and maintenance. The Final Environmental Impact Statement (FEIS) for the license noted that regular surveys for invasive aquatic weed species would be conducted as part of the Project’s Vegetation Management Plan. The term “aquatic weed” is used here to refer to any non-native aquatic plant species. Information from repeated aquatic surveys will help determine native species distributions and the need for treatment of problematic aquatic weed species, particularly hydrilla (Hydrilla verticillata), Brazilian elodea (Egeria densa), and Eurasian watermilfoil (Myriophyllum spicatum). Surveys conducted for PGE by Portland State University (PSU) in Timothy Lake, Lake Harriet, and North Fork Reservoir in 2011 did not locate any problematic submerged or floating leaved aquatic weed species. Earlier surveys of Timothy Lake, and Timothy Lake and Lake Harriet, also indicated the reservoirs were free of aquatic weeds. Heaton et al. (1996) noted that the native species Bidens beckii was present and had the potential to become weedy, however, this species was not found during the 2004 or 2011 surveys. This report covers the results of follow up aquatic vegetation surveys conducted in Lake Harriet, Timothy Lake, and North Fork Reservoir between August 14 and August 21, 2014, as well as new surveys of Faraday Lake and Estacada Lake. Shoreline surveys for emergent invasive species such as yellow flag iris (Iris pseudacorus) and purple loosestrife (Lythrum salicaria) were included in surveys for the first time. Title: 2014 Aquatic Weed Surveys in Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake Author: Miller, Rich, Sytsma, Mark D., Brittain, Jeffrey Thomas Year: 2014 The Clackamas River Hydroelectric Project No. 2195 (Project) is located on the Oak Grove Fork of the Clackamas River and the mainstem of the Clackamas River in Clackamas County, Oregon. Reservoirs included in the Project include Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake. The operator of the Project, Portland General Electric (PGE), was issued a license on December 21, 2010 by the Federal Energy Regulatory Commission (FERC) for continued operations and maintenance. The Final Environmental Impact Statement (FEIS) for the license noted that regular surveys for invasive aquatic weed species would be conducted as part of the Project’s Vegetation Management Plan. The term “aquatic weed” is used here to refer to any non-native aquatic plant species. Information from repeated aquatic surveys will help determine native species distributions and the need for treatment of problematic aquatic weed species, particularly hydrilla (Hydrilla verticillata), Brazilian elodea (Egeria densa), and Eurasian watermilfoil (Myriophyllum spicatum). Surveys conducted for PGE by Portland State University (PSU) in Timothy Lake, Lake Harriet, and North Fork Reservoir in 2011 did not locate any problematic submerged or floating leaved aquatic weed species. Earlier surveys of Timothy Lake, and Timothy Lake and Lake Harriet, also indicated the reservoirs were free of aquatic weeds. Heaton et al. (1996) noted that the native species Bidens beckii was present and had the potential to become weedy, however, this species was not found during the 2004 or 2011 surveys. This report covers the results of follow up aquatic vegetation surveys conducted in Lake Harriet, Timothy Lake, and North Fork Reservoir between August 14 and August 21, 2014, as well as new surveys of Faraday Lake and Estacada Lake. Shoreline surveys for emergent invasive species such as yellow flag iris (Iris pseudacorus) and purple loosestrife (Lythrum salicaria) were included in surveys for the first time. Close

• 10. [Article] Aquatic Invasive Plant Surveys in the BLM Medford District During 2012

  Aquatic plant surveys were conducted at 22 waterbodies located within the Bureau of Land Management’s Medford District during the summer of 2012. Sites included eleven lakes, ponds or reservoirs and six ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Invasive Plant Surveys in the BLM Medford District During 2012 Author: Miller, Rich, Morgan, Vanessa, Sytsma, Mark D. Year: 2013 Aquatic plant surveys were conducted at 22 waterbodies located within the Bureau of Land Management’s Medford District during the summer of 2012. Sites included eleven lakes, ponds or reservoirs and six reaches along the Rogue and Applegate Rivers. Five sampling areas surveyed during 2010 and 2011 were revisited to determine the extent of known non-native species infestations, positively identify rare species, or verify the absence of an expected non-native species. Plant specimens were collected at up to 50 sites at each waterbody using plant rakes or by observation. The non-native submersed species curly leaf pondweed (Potamogeton crispus) and Eurasian x northern watermilfoil (Myriophyllum sibiricum x spicatum) were widespread throughout the District. Eurasian watermilfoil (Myriophyllum spicatum) was present at two sites. Emergent non-native aquatic species included parrotsfeather (Myriophyllum aquaticum), yellow flag iris (Iris pseudacorus), purple loosestrife (Lythrum salicaria), reed canary grass (Phalaris arundinaceae), floating primrose-willow (Ludwigia peploides) and slender waternymph (Najas gracillima). Title: Aquatic Invasive Plant Surveys in the BLM Medford District During 2012 Author: Miller, Rich, Morgan, Vanessa, Sytsma, Mark D. Year: 2013 Aquatic plant surveys were conducted at 22 waterbodies located within the Bureau of Land Management’s Medford District during the summer of 2012. Sites included eleven lakes, ponds or reservoirs and six reaches along the Rogue and Applegate Rivers. Five sampling areas surveyed during 2010 and 2011 were revisited to determine the extent of known non-native species infestations, positively identify rare species, or verify the absence of an expected non-native species. Plant specimens were collected at up to 50 sites at each waterbody using plant rakes or by observation. The non-native submersed species curly leaf pondweed (Potamogeton crispus) and Eurasian x northern watermilfoil (Myriophyllum sibiricum x spicatum) were widespread throughout the District. Eurasian watermilfoil (Myriophyllum spicatum) was present at two sites. Emergent non-native aquatic species included parrotsfeather (Myriophyllum aquaticum), yellow flag iris (Iris pseudacorus), purple loosestrife (Lythrum salicaria), reed canary grass (Phalaris arundinaceae), floating primrose-willow (Ludwigia peploides) and slender waternymph (Najas gracillima). Close