Nitellopsis obtusa, Starry Stonewort -...

Nitellopsis obtusa,Starry

Stonewort

A Non-Native Submerged

Aquatic Lower Plant

• Scientific name of SSW: Nitellopsis obtusa (Desvaux in Loiseleur) J. Groves (1919)

• Common name: Starry Stonewort (SSW)

• Synonyms & Other Names: Chara obtusa, C. ulvoides, C. stelligera, Lychnothamnus stelliger, Nitella stelligera, N. stelligera var. ulvoides, N. ulvoides, N. bertolonii, Nitellopsisaculeolata, N. obtusa var. ulvoides, N. obtusa f. ulvoides, N. stelligera, Tolypellopsis obtusa, T. stelligera, T. ulvoides.

STARRY STONEWORT (SSW)Nitellopsis obtusa

• SSW is a nonindigenous submerged aquatic lower plant.

• SSW is a filamentous alga. It has straight branches arranged in whorls of 4 to 6 long branchlets, & are attached at acute angles to stem nodes.

• SSW is a summer annual, but can overwinter as a perennial during mild winters. However, SSW in some Michigan inland lakes appears to thrive in the cooler waters of fall, winter, & spring, & becomes dormant or less active during hottest parts of summer lakes (Pullman & Crawford 2010).


General Characteristics

• Most stem & branch cells are around 1 mm in diameter (Hargeby1990).

• Stems can extend up to 80 cm long, or 31.5 inches (Hargeby 1990).

• Growth up to 2 meters (6.5 ft) observed at depth of 9 m (29.5 ft) in one Michigan Lake (Pullman and Crawford, 2010).



Source: www.seagrant.sunysb.edu. SSW

http://www.seagrant.sunysb.edu/

The “squeeze test” may be used to distinguish SSW from Chara spp.

• In SSW, the protoplasm will pop out of the cell when squeezed. The remaining cell wall becomes limp straw (G. Douglas Pullman, Aquest Corp, personal communication).

• In Chara spp., the protoplasm does not separate easily from the cell wall (Hackett et al. 2014).



Source: Online photo. www.startribune.com. MI Dept. Environ. Quality. Chara sp., a native lake weed on left; SSW on right.

http://www.startribune.com/

• SSW has colorless hair-like filaments called rhizoids that act like roots (SSW does not have roots). The rhizoids attach the plant to an aquatic bottom in early life, but they frequently detach from an aquatic bottom to form a floating mat.

• Stoneworts have ability to absorb nutrients through all surfaces, not just the rhizoids (Holeck & Mills, 2007).

• SSW can be found at depths of 3-20 feet in lakes or slow moving rivers (Holeck & Mills, 2007).



• SSW plants can form gyrogonites, which are calcified, spiral-shaped fructifications (Bharathan1983, 1987).

• Another definition for gyrogonites from the online plain text English dictionary is the petrified fruit of Chara hispida, a species of stonewort.



SEM lateral & apical views of gyrogonites of :

• Chara aspera (figs.1-2);• C. hispida (figs. 3-4); • C. globularis (figs. 5-6)

Source:www.researchgate.net

STARRY STONEWORT (SSW)Nitellopsis obtusaGeneral Characteristics

http://www.researchgate.net/

http://www.researchgate.net/

STARRY STONEWORT (SSW)Taxonomic Classification

• EMPIRE……………………………………………...Eukaryota• KINGDOM)…………………………………………. Protista • PHYLUM………………………………………….... Charophyta• CLASS……………………………………….………Charophyceae• ORDER………………………………………………Charales• FAMILY………………………………………………Characeae• GENUS……………………………………………….Nitellopsis*• SPECIES……………………………………………..obtusa

*Other genera in the Characeae family include Chara, LamprothamniumLynchnothamnus, Nitella, & Tolypella.

Source: Lewis & McCount (2004).

STARRY STONEWORT (SSW)Taxonomic Classification Starry stonewort descriptionStoneworts used to be classified as members of the plant kingdom, but it is now agreed that they belong – along with other green algae – in the kingdom Protista. Put simply, the protistas are simple multi-celled or single celled organisms, descended from some of the earliest life-forms that appeared on Earth. Some of the Chlorophytes, specifically the stoneworts, are thought by scientists to have been the early ancestors of all plants. Stoneworts do indeed resemble plants, are frequently mistaken for them, and are often found as fossils.

Source:www.arkive.org/starry-stonewort/nitellopsis obtusa.

• SSW plants are dioecious, which means that plants are either male or female.

• The best evidence to date indicates that the SSW populations in the United States are all male, though there may be undiscovered females. This means that spread of SSW is probably through human movement of fragments from lake to lake.

• (See http://www.maisrc.umn.edu/starry-stonewort. For more information, contact Dr. Daniel Larkin, Asst. Professor & Extension Specialist at [email protected]).

• MAISRC stands for Minnesota Aquatic Invasive Species Research Center.

STARRY STONEWORT (SSW)Nitellopsis obtusaGeneral Life Cycle

http://www.maisrc.umn.edu/starry-stonewort

mailto:[email protected]

• SSW has orange female structures called oogoniathat are located at the nodes of upper branchlets.

• Male structures also are orange colored, & occur at nodes. They are called antheridia.


Source: www.algaebase.org. Online photo of pairedSSW oogonia. Collected by Emma Harris, Norfolk, UK.08-04-2014.

Source: Starry Stonewort (Nitellopsisobtusa) Biology & Management by ScottVan Egeren, Wisconsin DNR, July 29,2015. Photo from a slide presentationgiven in a public information meeting.www.dnr.wi.gov/topic/invasives/documents/ssw-info.pdf.

http://www.algaebase.org/

http://www.dnr.wi.gov/topic/invasives/

The dark red-colored oospores are female gametocytes from which an egg develops.

Source:www.wolverinelake.comA decade of starry stonewort in Michigan (Pullman, G. D. & G. C. Crawford, 2010).


http://www.wolverinelake.com/

• In sexual reproduction, plasmogamy (fusion of haploid gametes) is followed by karyogamy (nuclear fusion) to form a diploid zygote (Graham, L. E., & L. W. Wilcox. 1999).

• Sexual reproduction in SSW occurs through production & fertilization of oospores.

• Mature oospores usually are produced only under eutrophic conditions.

• Have a mandatory dormant period before germination (Bharathan1987; Hackett et al 2014).

• SSW spore production may be controlled by light & tends to take place from July to September.


• Asexual reproduction is a means by which an individual organism can produce additional copies of itself without unions of cytoplasmic nuclear materials or meiosis.

• One way SSW asexual reproduction occurs is by prolific production of vegetative bulbils.

• Creamy white bulbils may occur at the base of the main stem just below the substrate water interface, &

• On branches of the main stem at nodes.


• Bulbils stay viable for several years.

• They can be found at any point during the year.

• Most abundant in late fall & early spring (Pullman & Crawford 2010; Hackett et al 2014).

• Bulbils can sprout in 3-5 days under the right conditions (Bharathan 1987).


• Another way SSW asexual reproduction occurs is by possible plant fragmentation.

• One release indicates that SSW can easily reproduce from plant fragments (Houseman 2014).



Life Cycle With Zygotic MeiosisMost chlorophyceans & charophytes (includes Chara spp., & Nitellopsis obtusa)are primarily found in freshwaters. These algae have(1) haploid vegetative phases.(2) the zygote is the only diploid stage.(3) zygotic meiosis occurs. [After L. E. Graham & L. W. Wilcox. 1999.]

• SSW can be spread by oocytes.

• Oocytes could be easily transported in aquatic plant debris caught in boat trailers.

• Oocytes can easily become attached to the fur & feathers of aquatic fauna.

• An effective way for SSW to spread rapidly among inland lakes (Pullman & Crawford 2010).


Means of Spread of SSW

Aquatic plants hitching ride on a boat trailer. Michigan Dept. of Environmental Quality. MSU Extension. Online photo msue.anr.msu.edu.

• SSW could be spread by plant fragments, but there has been little research in this area.

• Believed pathways of SSW dispersal are attachment of fragments, oospores, & bulbils to animals & boats (Hackett et al 2014).

• Fragments of SSW can easily be spread between lakes by boats, trailers, waterfowl, & anchors holding sediments (Anonymous 2014; Ford-Steward 2015).

• SSW fragments may act as disseminules that could be important in the spread of the plant within a lake & from lake to lake (Pullman & Crawford 2010).




Means of Spread of SSW• SSW also can be spread

by star-shaped bulbils • Bulbils occur mainly at

the lower stem nodes near the substrate.

• Bulbils reach 4 mm across (about 0.2 in).

• Bulbils produce clones of the parent.

• Bulbils stay viable forseveral years (Hackett et al 2014).

Source: Online photo at www. uwsp.edu



• SSW may be spread in ballast water (Mills et al 1993).

• SSW was believed to have been introduced in ship ballast water into the St. Lawrence Seaway (Geis et al 1981; Schloesser et al 1986).

STARRY STONEWORT (SSW)Nitellopsis obtusa Distribution

Native Range: SSW is native to Eurasia, from the west coast of Europe to Japan (Mills et al 1993; Soulie-Marsche et al 2002). SSW is now in decline in parts of Europe & endangered in the UK (Hackett et al 2014) where it is afforded general protection under the Wildlife & Countryside Act, 1981.

Invaded: See Escobar et al 2016.


DistributionPresent: United States range includes much of the Great Lake Region & • Parts of the Upper Mississippi-Crow-Rum Basin • The Rock Basin • The Upper Illinois Basin • The Allegheny Basin • The Upper Susquehanna Basin • The St. Francois River Basin

(Source: U. S. Dept. of the Interior, U. S. Geological Survey. Nonindigenous Aquatic Species Database, Gainesville, Florida. URL:nas.er.usgs.gov.). This website actually lists collection information for 1547 SSW sites in the Great Lakes Region and other sites as listed here.


Present Range in the Great Lakes Region

• Status: SSW is established in Indiana, Michigan, Minnesota, New York, Pennsylvania, Vermont, & Wisconsin.

• SSW is not a problematic invasive in locations outside the St. Lawrence Seaway, Michigan, New York, & Indiana (Hackett et al 2014).

• Although SSW has established invasive populations in lakes in the above locations, little data have been published regarding ideal environmental conditions or nutrient levels that promote invasive SSW growth in lake ecosystems (Brown 2014). Most of what is known comes from observations (Hackett et al 2014).


DistributionPresent Range in the Great Lakes Region includes:

Michigan: 1st found in 1983 at Lake St. Clair, along the Saint Clair & Detroit Rivers (Schloesser et al 1986).

Source: Online photo www.riverlorian.com


Distribution (Michigan) • SSW now occurs at lakes

in all Lower Peninsula basins of Michigan.

• SSW has infested nearly 200 MI lakes, & has established invasive populations in over a 100 MI inland lakes (Hackett et al 2014).

• SSW also found in 2007 at Millecoquins Lake in Mackinac County of the Upper Peninsula of Michigan (Pullman & Crawford 2010).

Online photo www.Michigan.gov. (Hackett et al 2014). Green dots show reported presence of SSW on the Midwest Invasive Species Information Network (MISIN).

http://www.michigan.gov/


Part 1 of 2 Michigan Distribution 2016


Part 2 of 2 Michigan Distribution 2016


Distribution (Indiana) Present Range in the Great Lakes Region includes:

Indiana: Initially discovered in 2008 in Lake Wawasee (Edgell 2011; Aquatic Weed Control 2015).

• SSW occurred in 8 lakes in northeastern Indiana as of 2014 (Edgell 2011; Pearson 2015).


Indiana Distribution (USGS Data) &Information from Aquatic Weed Control

Indiana: Currently SSW is in 16 lakes in northern Indiana as of 2016:Elkhart Hunter Lake** 2016Elkhart Simonton Lake** 2016Kosciusko Lake Wawasee, Syracuse 2008 Established*Kosciusko Syracuse Lake, Syracuse 2011 EstablishedKosciusko Tippecanoe Lake, Oswego 2013 EstablishedKosciusko Webster Lake, North Webster 2015 EstablishedLaGrange Adams Lake, Wolcottville 2014 EstablishedLaGrange Wall Lake near town of Orland 2010 EstablishedLaGrange Cass Lake (near Middlebury, IN)** 2016* Established means population is reproducing & overwintering.** Source: Aquatic Weed Control, 9-19-2016.


Indiana Distribution (USGS Data) &Information from Aquatic Weed Control

Indiana: Currently SSW is in 16 lakes in northern Indiana as of 2016:

LaPorte Hudson Lake*** 2016Steuben Crooked Lake, Angola 2011 Established*Steuben Jimmerson Lake, Angola 2012 EstablishedSteuben Lake George at Ind/MI border 2009 EstablishedSteuben Lake Pleasant** 2015 EstablishedSteuben Lake James(lower basin near Glen Eden Channel) 2016 EstablishedSteuben Snow Lake*** 2016* Established means population is reproducing & overwintering.**Just behind boat launch in end of channel by the marina.*** Source: Aquatic Weed Control, 9-19-2016.


Distribution (Indiana)

Present Range in the Great Lakes Region includes

Indiana: Presence of SSW in a county indicated by a blue circle. Sixteen occurrences of SSW in 2016 as follows:

Steuben County: SSW in 6 lakes

LaGrange County: SSW in 3 lakes

Elkhart County: SSW in 2 lakes

Kosciusko County: SSW in 4 lakes

LaPorte County: SSW in 1 lake Indiana County Map


Indiana Distribution 2016


Minnesota: Now 10 known occurrences (MN DNR 2015 & 2016; 2016 USDI, USGS Nonindigeous Aquatic Species Database).Stearns County Mud Lake 2015 Established*Stearns County Rice Lake 2016 EstablishedMeeker County Lake Koronis 2015 EstablishedBeltrami County Turtle Lake 2015 EstablishedBeltrami County Upper Red Lake 2016 EstablishedBeltrami County Cass Lake 2016 EstablishedBeltrami County Moose Lake 2016 EstablishedCass County Lake Winnibigodhish 2016 EstablishedItasca County Lake Winnibigodhish 2016 EstablishedWright County West Lake Sylvia 2016 Established

*Established means population is reproducing & overwintering.NOTE: Minn DNR news release confirms 2 more Minn. Lakes with SSW (Times Staff Report 8-25-2016). The Minn. DNR states that SSW is typically spread by lake users who transport fragments from 1 water body to another (St. Cloud Times). See www.mndnr.gov/ais.

http://www.mndnr.gov/ais


Distribution (Minnesota)Present Range in the Great Lakes Region includesMinnesota: Presence of SSW in a county indicated by a blue circle. Ten occurrences of SSW in 2016 as follows:

Stearns County- SSW in 2 lakes

Meeker County – SSW in 1 lake

Beltrami County – SSW in 4 lakes

Cass County – SSW in 1 lake

Ithasca County – SSW in 1 lake

Wright County – SSW in 1 lake


Minnesota Distribution 2016


Distribution (New York) Present Range in the Great Lakes Region includes:

New York:

• First spotted in North America in 1978 along the St. Lawrence River (Geis et al. 1981; Mills et al. 1993).

• Found in 1981 at Lake Ontario (iMapInvasives 2015).

New York: As of 2015, SSW found in 17 counties at 31 sites, including 16 inland lakes, 7 sites in the St. Lawrence River, & 8 sites in Lake Ontario (Sleith et al 2015).

Online photo: blogs.nybg.org. Robin Sleith algae sample sites of 400 lakes in New York State in 2014 for SSW & other green algae. SSW not found within boundaries of Adirondack Park (Sleith et al 2015).

STARRY STONEWORT (SSW)

Nitellopsis obtusaDistribution


New York Distribution 2016


Distribution (Pennsylvania)Present Range in the Great Lakes Region includes:

Pennsylvania: Two occurrences (Jim Grazio, PA DEPT., personal communication 2015; 2016 USDI, USGS Nonindigeous Aquatic Species Database; & Sea Grant Pennsylvania).

Erie County Presque Isle Bay 2009 Seen Established*

Erie County Presque Isle Bay 2012 Confirmed Established

Butler County Lake Arthur 2016*** Established means population is reproducing & overwintering.**Source: Starry Stonewort Nitellopsis obtusa, Sea Grant Pennsylvania. www.seagrant.psu.edu


Distribution (Pennsylvania)Present Range in the Great Lakes Region includes:

Pennsylvania: Presence of SSW in a county indicated by a blue circle. Two occurrences of SSW in 2016:

Erie County – 1 Lake

Butler County – 1 LakeCounty Map of State of Pennsylvania


Pennsylvania Distribution 2016


Distribution (Vermont)Present Range in the Great Lakes Region includes:

Vermont: Two occurrences (FLOW 2015; 2016 USDI, USGS Nonindigeous Aquatic Species Database).

Orleans County Memphremagog Lake 2015 Established*(Small cove in SE portion)

Orleans County Lake Derby, public boat access 2016 Established

* Established means population is reproducing & overwintering.


Distribution (Vermont)Present Range of SSW in the Great Lakes Region includes:

Vermont: Presence of SSW in a county indicated by a blue circle. Two SSW occurrences :

Orleans County – 2 Lakes

County Map of State of Vermont


Vermont Distribution 2016

STARRY STONEWORT (SSW)Nitellopsis obtusa Distribution (Wisconsin)

Present Range in the Great Lakes Region includesWisconsin:17 occurrences of SSW in last 3 years (WI DNR 2014 & 2015;

2016 USDI, USGS Nonindigenous Aquatic Species Database).

Waukesha Little Muskego Lake 2014 EstablishedWaukesha Big Muskego Lake, near boxhorn Dr. 2015 EstablishedWaukesha Bass Bay Lake 2015 EstablishedWaukesha Muskego Creek 2015 EstablishedWashington Pike Lake at Lake Drive boat landing 2015 EstablishedWashington Silver Lake 2015 EstablishedWashington Green Lake, South Public Boat Launch 2016 EstablishedRacine Long Lake, boat landing 2015 Established

*Source: Lee Bergquist, Milwaukee Journal Sentinel, August 31, 2016. Starry stonewort found in Sturgeon Bay. The State Department of Natural Resources says starry stonewort, a fast-growing invasive aquatic plant that can upend the ecosystem in affected lakes, has been found for the first time in Lake Michigan. (www.jsonline.com.)

STARRY STONEWORT (SSW)Nitellopsis obtusa Distribution (Wisconsin)

Present Range in the Great Lakes Region includesWisconsin:17 occurrences of SSW in last 3 years (WI DNR 2014 & 2015;

2016 USDI,USGS Nonindigenous Aquatic Species Database).

Door Sturgeon Bay Ship Canal, Lake Michigan 2016 EstablishedDoor Little Sturgeon Bay, Lake Michigan near Henderson Point 2016 EstablishedDoor Fish Creek, Green Bay, Lake Michigan near public boat ramp 2016 EstablishedDoor Channel around Hi-Cliff Park, W. of Idlewild 2016 EstablishedDoor Rowley Bay, Lake Michigan, near public boat ramp 2016 EstablishedDoor Potawtomi State Park, Sawyer Harbor, Sturgeon Bay 2016 EstablishedDoor Sawyer Harbor, North Shore, Sturgeon Bay 2016 EstablishedDoor Ellison Bay, Green Bay, near public boat ramp 2016 EstablishedDoor Sister Bay, Green Bay, near public boat ramp 2016 Established

Source: Lee Bergquist, Milwaukee Journal Sentinel, August 31, 2016. Starry stonewort found in Sturgeon Bay. The State Department of Natural Resources says starry stonewort, a fast-growing invasive aquatic plant that can upend the ecosystem in affected lakes, has been found for the first time in Lake Michigan. (www.jsonline.com.)


Distribution

Present Range in the Great Lakes Region includes

Wisconsin: Presence of SSW in a county indicated by a blue circle. Seventeen occurrences of SSW in lakes as of 2016:

Waukesha County- SSW in 4 lakes

Washington County – SSW in 3 lakes

Racine County – SSW in 1 lake

Door County – SSW in 9 lakes

County Map of Wisconsin


Wisconsin Distribution 2016


USDI, USGS 2016 SSW DistributionFrom Animated Map of NAS Data


Distribution (USGS Data)

NOTE: These data are preliminary or provisional and are subject to revision. They are being provided to meet the need for timely best science. The data have not received final approval by the U. S. Geological Survey (USGS) and are provided on the condition that neither the USGS nor the U. S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the data.


Ecological Impacts of SSW• SSW reduces the diversity of plants.

• It is a highly aggressive aquatic lower plant that is able to out-compete all other Michigan aquatic plant species, including all invasive species & current alien species (Hackett et al 2014).

• SSW can alter or eliminate native submerged aquatic plants.

• Once established in inland lakes, SSW forms dense mats of vegetation that completely cover the lake bottom (USDI, USGS. 2016).

• These dense mats act as benthic barriers accumulating phytotoxins & making sediments inhospitable for plant growth until conditions change (Pullman & Crawford 2010).

Lake Wawasee Historical Tier II DataNumber of Native Plant Species

0

2

4

6

8

10

12

14

16

18

0

2

4

6

8

10

12

14

16

18

14

18

16

14

16 1615

1413

1514 14

13

1514 14

5/26/2005 8/10/2005 7/26/2006 8/12/2009 6-22-2011 9/8/2011 5/30/2012 8/22/2012 6/7/2013 8/16/2013 6/5/2014 8/26/2014 611/2015 8/26/2015 6/13/3016 8/22/2016

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Syracuse Lake Historical Tier II DataNumber of Native Plant Species

0

2

4

6

8

10

12

14

16

0

2

4

6

8

10

12

14

16

10

12

14

15

12

16

12

16

13

10

13 1312 12

1314

8/19/2004 8/5/2005 8/9/2006 8/12/2009 6-29-2011 8/25/2011 6-1-2012 8/16/2012 6/11/2013 8/9/2013 6/4/2014 8/15/2014 6/5/2015 7/20/2015 6/8/3016 8/4/2016

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Sample Dates

LAKE WAWASEE HISTORIAL TIER II DATANATIVE SPECIES DIVERSITY 2005 TO 2016

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0.75

0.86

0.99

0.830.88 0.88 0.88 0.87

0.83 0.84 0.82 0.82 0.810.85

0.810.84

5/26/2005 8/10/2005 7/26/2006 8/12/2009 6-22-2011 9/8/2011 5/30/2012 8/22/2012 6/7/2013 8/16/2013 6/5/2014 8/26/2014 611/2015 8/26/2015 6/13/3016 8/22/2016

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Sample Dates

SYRACUSE LAKE HISTORICAL TIER II DATANATIVE SPECIES DIVERSITY 2004 to 2016

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

0.76

0.82

0.880.84 0.83 0.82

0.79

0.85

0.770.8

0.83 0.830.78

0.83 0.83 0.83

8/19/2004 8/5/2005 8/9/2006 8/12/2009 6-29-2011 8/25/2011 6-1-2012 8/16/2012 6/11/2013 8/9/2013 6/4/2014 8/15/2014 6/5/2015 7/20/2015 6/8/3016 8/4/2016

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Sample Dates

LAKE WAWASEE HISTORICAL TIER II DATANO. SITES WITH NATIVE PLANTS 2005-2016

0

50

100

150

200

250

300

350322 320

8871

116 113 113 116102

121110 106 111 106 97

117

5/26/2005 8/10/2005 7/26/2006 8/12/2009 6-22-2011 9/8/2011 5/30/2012 8/22/2012 6/7/2013 8/16/2013 6/5/2014 8/26/2014 611/2015 8/26/2015 6/13/3016 8/22/2016

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SAMPLE DATES

SYRACUSE LAKE HISTORICAL TIER II DATANO. SITES WITH NATIVE PLANTS 2005-2016

0

10

20

30

40

50

60

70

80

90

100

73

63

74

9289

78

9285

82 8285

78 7975 77

8/19/2004 8/5/2005 8/9/2006 8/12/2009 6-29-2011 8/25/2011 6-1-2012 8/16/2012 6/11/2013 8/9/2013 6/4/2014 8/15/2014 6/5/2015 7/20/2015 6/8/3016 8/4/2016

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SAMPLE DATES


Ecological Impacts of SSW• SSW mats have been observed to negatively affect fish

reproduction behavior by compromising nesting & feeding habitat (Hackett et al 2014).

• Dense mats of SSW directly impact the habitat used by native fish for spawning.

• Bass and sunfish are known to regularly spawn in dense growth of native Chara sp., but these spawning behaviors did not occur in correspondingly dense growths of SSW (Pullman & Crawford 2010).


Ecological Impacts of SSW• In Charophyte meadows, SSW utilizes & precipitates

calcium carbonate causing immobilization of phosphorus, inhibiting primary production (Kufel, L., & I. Kufel. 2002).

• In Charophyte meadows, SSW increased water clarity by minimizing re-suspension of particulate matter (Kufel, L., & I. Kufel. 2002).

• SSW can become a navigational nuisance in shallow waters.


Socio-Economic Impact of SSW

Nitellopsis obtusa is a relatively new invasion, particularly to the inland lakes. The long term impacts on the economic value of lake property cannot yet be properly assessed (USDI, USGS. 2016).


Management of SSW• Prevention

• Preventing the establishment of SSW is preferable to post-establishment management (Hackett et al 2014).

• In Michigan, SSW is 1 of 13 plant species that may neither be sold nor grown in the state under the Natural Resources & Environment Protection Act 451 of 1994; includes plants, fragments, seeds, or a hybrid or genetically engineered variant thereof (MI Dept. of Agriculture & Rural Develop., Prohibited & Restricted Weeds; Hackett et al 2014).



• Some actions that may prevent & limit the dispersal of SSW include:

• providing boat washing stations for high-traffic public lake accesses.

• developing & sustaining a water recreation vehicle & trailer inspection program (Hackett et al 2014).



• If boat washing stations & inspection programs are not available, other actions individuals can take when leaving a lake or river that may prevent or limit the dispersal of aquatic invasive spp. (www.dnr.state.mn.us/invasive/ais/infested.html) include:

• Clean all aquatic plants, zebra mussels, & other invasive species from boats, trailers, & water-related equipment (includes fishing gear).

• Drain water from your boat, ballast tanks, motor, live well & bait container. Remove drain plugs & keep drain plugs out while transporting equipment.

• Dispose of unwanted bait in the trash. To keep live bait, drain the water & refill the bait container with bottled water or tap water.

http://www.dnr.state.mn.us/invasive/ais/infested.html


Management of SSW

• Biological

• There are no known biological controls for SSW (Pullman & Crawford 2010).


Management of SSWMechanical:Mechanical harvesting of SSW is difficult because

(1) Dense growthquickly fills harvesters.

(2) Recolonization is fast if adjacent population remain (Pullman & Crawford 2010).

(3) Might produce plant fragments that could be important in the spread of the plant.

Source: www.mlive.com. LEONI, MI.(Jackson County). In an effect to cut down on the use of chemicals in Center Lake, the Clearwater Lake Assoc. began using a different method for clearing aquatic plants.

http://www.mlive.com/

STARRY STONEWORT (SSW)Nitellopsis obtusa Management of SSW

Other Management (Physical):• Hand pulling and diver assisted suction harvest could be employed

in small new infestations if found early (spot treatment). At Little Muskego Lake in Wisconsin, diver assisted suction harvesting continues to remove invasive SSW from key areas of the lake. See http://dnr.wi.gov/news/releases/article/?id=3700.

• Techniques such as drawdown of water level or shading may limit SSW growth, but have yet to be examined (Hackett et al 2014).

• Stonewort grows rapidly & is very difficult to eradicate. In fact, Minnesota DNR say it has never been eradicated from a lake in the U. S. (www.mprnews.org., August 31, 2016).

http://www.mprnews.org/


Management of SSW• Management – Chemical

• SSW is highly sensitive to copper & endothall chemical treatments, but no treatments have been developed for complete lake eradication (Hackett et al 2014).

• Application rates recommended for Chara control on U.S. EPA approved pesticide labels appear to be sufficient to control low growing SSW (Pullman & Crawford 2010).

• If SSW is growing in a dense mat, only the top layer will dieback with a standard treatment.


Management of SSW• Management – Chemical

• Chemical treatments mixed with chelating agents may also be used to treat deeper into the mats (Pullman & Crawford 2010).

• More research may be needed to find better methods to manage SSW. Eradication is not a realistic goal at this time. Research is ongoing at Clemson University on the management of freshwater algae like SSW, though they were delayed in starting due to difficulty growing SSW in a laboratory setting (G. Douglas Pullman, Aquest Corp., personal communication) (Hackett et al 2014).

Source: Online photo www.wawaseepoa.org. Dr. Nate Bosch giving a presentation at the Annual Meeting of the Syracuse Lake Assoc. on 08-06-2016.


Management of SSWRESEARCH:Dr. Nate Bosch, Director of the Center for Lakes & Streams, Grace College, Warsaw, IN presented a program on current threats & strategic effects of aquatic plant species in Syracuse Lake. The Center’s program includes SSW application research & a blue-green algae study.

Dr. Bosch presented a current map which showed 210 acres of SSW in Syracuse Lake. Current research to develop means to control the spread of SSW was noted.

http://www.wawaseepoa.org/


History & Management Efforts Lake Wawasee & Syracuse Lake

• 2008- SSW was first observed in summer 2008 on Lake Wawasee in the channels west side of Johnson Bay.

• 2009- (August)- Treatment of 15 acres in Johnson’s Bay using Nautique herbicide for control of SSW.

• 2010- Treatment of 20 acres in Johnson’s Bay using Nautiqueherbicide at 0.8 ppm copper (=2.4 gal/acre ft) for control of SSW.


History/Management Efforts Lake Wawasee & Syracuse Lake• NAUTIQUE is an aquatic herbicide. The active ingredients are:

• Copper Ethylenediamine Complex (Case# 13426-91-0) at 13.2%• Copper Triethanolamine Complex (Case# 82027-59-6) at 14.9%• Other Ingredients at 71.9%. Metallic copper equivalent equals 9.1%. Signal word is

danger.• Application rates of Nautique is in the following table from the label:



• 2011- Three small test areas in Johnson’s Bay were treated with varying rates & formulations of Cutrine Ultra & Hydrothol herbicides.• It was determined from these tests that using Cutrine Ultra at the

rate of 2.4 gal per acre-foot in combination with Hydrothol 191 at the rate of 1 quart per surface acre was the most effective treatment.

• On September 16, 2011, 4 areas in Johnson’s Bay were treated with this new herbicide prescription.


History/Management Efforts Lake Wawasee & Syracuse Lake

CUTRINE-ULTRA is a algaecide/herbicide/cyanobactericide. The active ingredients are:

• Copper Ethanolamine Complex, Mixed at 27.8%.• Other Ingredients at 72.2%. Contains 0.9 lbs. of elemental

copper per gallon. Metallic copper equivalent, 9%. • Signal word is danger.• Rate & Copper PPM (following table from label):


History/Management Efforts Lake Wawasee & Syracuse Lake• HYDROTHOL 191 is an aquatic algaecide & herbicide. The

active ingredients are:• Mono(N,N-dimethylalkylamine) salt of endothall at 53.0%.• Other Ingredients at 47.0%. Contains 2 lbs. endothall acid / gal.• Signal word is danger.• Generally rates of 0.05 to 0.3 ppm (0.6–3.6 pints are effective for control of algae:

following table from label).



• 2011- SSW was first discovered in Syracuse Lake in the 4.5 acre access channel adjacent to Syracuse Henry Ward Park.

• 2011- IDNR received grant through Great Lake Restoration Initiative for control of exotic aquatic plant species.

• Since 2011, the IDNR has fully funded numerous SSW treatments on both Lake Wawasee & Syracuse Lake.

• These treatments have used a combination of Cutrine Ultra herbicide at the rate of 2.4 gal per acre foot with Hydrothol 191 herbicide at various rates to control SSW.

2014 SYRACUSE LAKE SSW DISTRIBUTION.

Total SSW surface acres on 6-4-2014estimated at48.22 acres.



• 2014- On 7-10-2014, Aquatic Weed Control treated 17.49 acres of Syracuse Lake with Cutrine Ultra at 2.4 gal per acre foot in combination with hydrothol herbicide.

• 2014- On 8-5-2014, repeated treatments at Syracuse Lake using same herbicides & rates.

• These treatments funded through the Great Lakes Restoration Initiative (GLRI).

• Cost for SSW treatments in 2014 was $787.47 per 10 acre-feet treated.



• 2015 - There was a total of 48.22 acres of SSW in Syracuse Lake.

• SSW also was common to most of the littoral zone of the lake.

• This acreage represents 11.65% of total lake acreage of 414 acres.



• 2015- On 7-1-2015, a total of 17.98 acres of SSW infestation in Syracuse Lake was treated with Cutrine Ultra at the rate of 2.4 gal per acre foot in combination with Hydrothol herbicide.

• This acreage includes all areas of the “Syracuse Lake 2015 SSW Treatment map”.

2015 SYRACUSELAKE SSWLOCATIONS

Blue areas treatedin 2014.

Green area 7 a new area for 2015.

Tier II SSW surveylocations shown as labeled green dots.



• 2015- On 8-4-2015, a total of 8.58 acres of SSW infestation in Syracuse Lake was treated with Cutrine Ultra at the rate of 2.4 gal per acre foot in combination with Hydrothol herbicide.

• This treatment comprised of areas 1,5,& 7 on the Syracuse Lake 2015 SSW treatment map.

• All SSW treatments in 2015 were funded through the Great Lakes Restoration Initiative (GLRI).



• 2016- On June 08, there was a total of 210.07 acres of SSW in Syracuse Lake. This amount represents 50.74 % of the total lake acreage of 414 acres. • On July 11, 2016, three areas totaling 8.51 acres were treated with

Cutrine-Ultra at a rate of 2.4 gallons/acre foot in combination with hydrothol herbicide. See enclosed map.

• On August 31, 2016, the same three areas of SSW infestation were treated with the same above materials at the same rates. See map.

• All SSW treatments in 2016 were funded through the Great Lakes Restoration initiative (GLRI).

2016 SYRACUSELAKE SSW DISTRIBUTION

• SWW acreageestimated at 210.07 acres as of 6-8-16.

• Tier II SSW survey locations shown as labeled green dots.

• Past treatmentareas shown in blue.

2016 SYRACUSE LAKE SSW TREATMENT AREAS

• In 2016, three areas totaling 8.51 acres were treated once in July and once in August with Cutrine-Ultra at the rate 2.4 gal per acre-foot in combination with hydrothol herbicide.

• This acreage includes all areas shown on this SSW map.

2016 SYRACUSELAKE SSW DISTRIBUTION

• SSW acreage estimated at 210.07 acres as of 6-8-2016.


2016 SYRACUSELAKE SSW DISTRIBUTION• SSW acreage

estimated at 219.10 acres as of 8-4-2016


SYRACUSE LAKE SSWOCCURRENCE OF SSW AT 0-20 FT LAKE DEPTH

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8/19/2004 8/5/2005 8/9/2006 8/12/2009 6/29/2011 8/25/2011 6/1/2012 8/16/2012 6/11/2013 8/9/2013 6/4/2014 8/15/2014 8-22-2015 6/5/2015 7/20/2015 8/4/2016

SSW

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RED = ALL DEPTHSGREEN = 0 TO 5 FTPURPLE = 5 TO 10 FTYELLOW = 10 TO 15 FTBLUE = 15 TO 20 FT

SYRACUSE LAKE SSWSURFACE ACRES WITH SSW

0

50

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4.5 7.513.21

48.22 48.22

219.1

2011 2012 2013 2014 2015 2016

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SYRACUSE LAKE SSWPERCENT OF 414 SURFACE LAKE ACREAGE

0

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1.09 1.81 3.19

11.65 11.65

52.92

2011 2012 2013 2014 2015 2016

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SYRACUSE LAKE SSWSURFACE ACRES WITH SSW & ACRES TREATED

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2011 2012 2013 2014 2015 2016

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• 2014- On 7-(9 & 11)-2014, Aquatic Weed Control treated 113.4 acres of Lake Wawasee SSW with Cutrine Ultra at 2.4 gal per acre-foot in combination with hydrothol herbicide.

• 2014- On 8-(5 & 6)-2014, repeated treatments at Lake Wawaseeusing same herbicides & rates.

• Areas 9,11, nw area sec.12,14,21,27,28,29 on Lake Wawasee were not treated.

• These treatments funded through the Great Lakes Restoration Initiative (GLRI).

• Cost for SSW treatments in 2014 was $787.47 per 10 acre-feet treated.

2014 LAKE WAWASEESSW DISTRIBUTION

SSW acreage on08-29-2014 estimatedat 198.86 acres.



• 2015- In 2015 there was a total of 223.73 acres of SSW in Lake Wawasee along with many new open water sites. This figure represents an increase of 24.87 acres since 2014.

• This acreage also represents 7.31% of the total lake acreage (3060 acres).

• Some 108.6 acres were treated.

2015 LAKE WAWASEESSW DISTRIBUTION

• Total SSW surface acres on 06-12-2015estimated at 223.73 acres.

• Areas shaded in blue treated in 2014.



• 2016- On 6-13-2016, there was a total of 233.99 acres of SSW in Lake Wawasee, which represents 7.65 % of the total lake acreage of 3060 acres.

• 2016- On 7-11-2016, 100.7 acres were treated (first treatment).

• 2016- On 8-31-2016, 48.0 acres were treated (second treatment).

• All SSW treatments in 2016 were funded through the Great Lakes Restoration Initiative (GLRI).

2016 LAKE WAWASEE SSWAREAS• 1st treatment: On

7-11-2016, 100.7 acres of SSW were treated with Cutrine-Ultra at the rate 2.4 gal per acre-foot in combination with hydrotholherbicide.


2016 LAKE WAWASEE SSWAREAS• 2nd treatment: On

8-31-2016, 48 surface acres of SSW were treated with Cutrine-Ultra at the rate 2.4 gal per acre-foot in combination with hydrotholherbicide.


2016 LAKE WAWASEE SSWAREAS

• Total SSW acreage on 6-13-2016 was233.99 acres along with many new open water sites.

• Spring 2016 tier II SSW survey sites shown as numbered green dots.

• Recent treatmentareas shown in blue.Treated on 7-11-2016.

2016 LAKE WAWASEE SSWAREAS

• Total SSW acreage on 8-22-2016 was238.9 acres along with many new open water sites. (This acreage is about the size of 181 football fields).

• Summer 2016 Tier II SSW survey sites shown as numbered green dots.

• Recent treatmentareas shown in blue; all other SSW beds shownin green.

All Depths = Red0 to 5 ft = Green5 to 10 ft = Blue10 to 15 ft = Yellow 15 to 20 ft = Turquoise20 to 25 ft = Purple

LAKE WAWASEE SSWOCCURRENCE SSW AT 0-25 FT LAKE DEPTHS

0

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5/26/2005 8/10/2005 7/26/2006 8-12-2009 6-22-2011 9-8-2011 5-30-2012 8-22-2012 6-7-2013 8-16-2013 6-5-2014 8-26-2014 6-11-2015 8-26-2015 6-13-2016 8-22-2016

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LAKE WAWASEE SSWSURFACE ACRES WITH SSW

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015 20

56

159

180.7198.86

223.73238.9

2008 2009 2010 2011 2012 2013 2014 2015 2016

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LAKE WAWASEE SSWPERCENT OF 3060 LAKE ACREAGE

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2

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8

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0.49 0.65

1.83

5.2

5.91

6.5

7.31

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Management Efforts Lake Wawasee 2016 SSW Test Plots

• In addition to the regular SSW treatments, there were herbicide trials to evaluate the effectiveness of several different herbicides on SSW by Aquatic Weed Control.

• There were 16 different test plots chosen with most being around 1 surface acre. Each plot was treated 2 times in 2016.

• These test plots are all shown on the following map. Herbicides used include Cutrina Ultra, Hydrothol, Clearigate, Clipper, and Algimycin. Information on the last 3 herbicides will follow.

2016 LAKE WAWASEE SSW HERBICIDETEST PLOTS

• Herbicides used in 12 test plots are shown on this map.

• There were 4 control plots.

• Treatments were made on June 27, 2016 & August 1, 2016.

• Sixteen test plots about 1 acre in size.12 plots with herbicide treatments, 4 control plots.

• Information on latitude & longitude of plots, & plot divisions not shown.

2016 LAKE WAWASEE SSW HERBICIDETEST PLOTS


Management Efforts Lake Wawasee SSW Test Plots

• CLEARIGATE, an aquatic herbicide, is a chelated copper formulation containing an emulsified surfactant/penetrant for highly effective control of coarse (thick call-walled) filamentous algae, muscilaginous (colonial) planktonic algae. The active ingredients are:

• Copper as elemental………………………………………………3.825%

• Inert Ingredients……………………..……………………….….96.175%


Management Efforts Lake Wawasee SSW Test Plots• Application rates of Clearigate are in the following table from the

label:



• CLIPPER is a contact herbicide for the management of undesirable aquatic vegetation in slow moving or quiescent waters. It is a water dispersible granule containing 51% active ingredient:

• Flumioxazin..………………..………………………………………51%

• Other Ingredients……………………………………………….….49%

STARRY STONEWORT (SSW) Nitellopsis obtusaManagement Efforts Lake Wawasee SSW Test Plots

• CLIPPER herbicide will control certain floating and emerged weeds and algae as listed on label when applied as a broadcast spray with appropriate equipment at 6 to 12 ounces of formulated product per acre plus adjuvant approved for use in aquatics. For best results apply Clipper herbicide to the foliage of actively growing weeds.

• CLIPPER herbicide will control certain submerged and floating weeds and algae as listed on label when applied subsurface with appropriate equipment at a rate that will produce an initial concentration of 200 to 400 ppb (of active ingredient) in the water column.



• ALGIMYCIN-PWF is a liquid water soluble algaecide/cyanobacteriocide that controls a broad range of algae & cyanobacteria growth in potable water reservoirs, ponds, lakes, irrigation conveyance systems, ditches, canals, & laterals.

• The active ingredients are:• Chelates of copper gluconate (Cas # 527-09-3)….………12.5%• Chelates of copper citrate (Cas #10402-15-00)…………..12.9%• Inert Ingredients……………………………….………………74.6%

• Contains 5% copper, 0.512 lbs. of copper per gallon (62g/l)


Management Efforts Lake Wawasee SSW Test Plots• ALGIMYCIN-PWF DOSAGE RATES FROM LABEL:

LITERATURE CITEDESCOBAR, LUIS E., HUIJIE QUAO, NICHOLAS B. D. PHELPS, CARLI K. WAGNER, & DANIEL J. LARKIN. 2016. Realized niche shift associated with the Eurasian Charophyte Nitellopsis obtusa becoming invasive in North America. Scientific Reports 6, Article No. 29037. 36 pp.

FORD-STEWARD, JANE. 2015. Aquatic experts gather to devise battle plan for new pest found in Little Muskego Lake. MuskegoNow. 4 pp. http://mymuskegonow.com/topstories/291726471.htm.

FLOW. 2015. New aquatic invasive species in Lake Memphremagog. Vermont Department of Environmental Conservation, Watershed Management Division, Montpellier, VT. (http://vtwatershedblog.com/2015/09/16/new-aquatic-invasive-species-confirmed-in-lake-memphremagog/. Created 9/16/2015. Accessed 9/17/2015.

GEIS, J. W., G. J. SCHUMACHER, D. J. RAYNAL, & D. P. HYDUKE. 1981. Distribution of Nitellopsis obtusa (Charophyceae: Characeae) in the St. Lawrence River: a new record for North America. Phycologia 20: 211-214.

GRAHAM, LINDA. E., & LEE W. WILCOX. 1999. Algae. Prentice Hall, Inc. 700 p.

HACKETT, R. A., CARON, J. J., & A. K. MONFILS. 2014. Status and strategy for Starry Stonewort (Nitellopsis obtusa (D. A. Desvaux) J. Groves) Management. Michigan Dept. Of Environmental Quality, Lansing, Michigan.

http://mymuskegonow.com/topstories/291726471.htm

http://vtwatershedblog.com/2015/09/16/new-aquatic-invasive-species-confirmed-in-lake-memphremagog/

http://vtwatershedblog.com/2015/09/16/new-aquatic-invasive-species-confirmed-in-lake-memphremagog/

LITERATURE CITED

HARGEBY, A. 1990. Macrophyte associated invertebrates & the effect of habitat permanence. Oikas 57(3):338-346.

HOLECK, KRISTEN, & ED MILLS. 2007, Starry Stonewort (Nitellopsis obtusa) Oneida Lake Status: Localized. Cornell Biological Field Station. 1 p.

HOUSEMAN, SUSAN. 2014. Starry Stonewort. The GLQO watershed Journal 8(4): 1-7. Website glgo.net.

iMAPINVASIVES. 2015. IMapInvasives New York. IMapInvasives. www.nymapinvasives.org. Created on 07/08/3025. Accessed on 07/08/2015

KIPP, E. M., M. McCARTHY, A. FUSARO, & I. A. PFINGSTEN. 2016. Nitellopsis obtusa. USDI, USGS Nonindigenous Aquatic Species Database, Gainesville, FL (http://nas.er.usgs.gov/FactSheet. Aspx?speciesID=1688. Revision Date:6/21/2016

KUFEL, L., and I. KUFEL. 2002. Chara beds acting as nutrient sinks in shallow lakes – a review. Aquatic Botany 72: 249-260.

LEWIS, L. A. & R. M. McCOUNT. 2004. Green Algae and the Origin of Land Plants. American Journal of Botany 91(10): 1535-1556.

http://www.nymapinvasives.org/

http://nas.er.usgs.gov/FactSheet

LITERATURE CITEDMILLS, E. L., J. H. LEACH, J. T. CARLTON, & C. L. SECOR. 1993. Exotic species in the Great Lakes: a history of biotic crises and anthropogenic introductions. Journal of Great Lakes Research 19 (1): 1-54.

MINNESOTA DEPARTMENT OF NATURAL RESOURCES (MN DNR). 2015. Invasive species starry stonewort confirmed in Stearns, Meeker county lakes. Minnesota Department of Natural Resources, St, Paul, MN.

MINNESOTA DEPARTMENT OF NATURAL RESOURCES (MN DNR). 2016. Starry Stonewort (Nitellopsis obtusa). Minnesota Department of Natural Resources, St. Paul, MN.)(www.dnr.state.mn.us/invasives/aquaticplants/starrystonewort/index/html)

PEARSON, J. 2015. DNR limiting weed control at Lake Tippecanoe. Indiana Department of Natural Resources. Indianapolis, IN.

PULLMAN, G. DOUGLAS, & GARY CRAWFORD. 2010. A Decade of Starry Stonewort in Michigan. Summer 2010 Lakeline Report. p. 36-42.

SCHLOESSER, D. W., P. L. HUDSON, & S. JERRINE NICHOLS. 1986. Distribution and habitat of Nitellopsis obtusa (Characeae) in the Laurentian Great Lakes. Hydrobiologia 133: 91-96.

http://www.dnr.state.mn.us/invasives/aquaticplants/starrystonewort/index/html

LITERATURE CITED

SLEITH, R. R., A. J. HAVENS, R. A. STEWART, & K.G.HSROL. 2015. Distribution of Nitellopsis obtusa (Characeae) in New York. Brittonia 67(2): 166-172. doi:10.1007/s12228-015-9372-6.

SOULIE-MARSCHE, I. M. BENAMMI, & P. GEMAYEL. 2002. Biogeopraphy of living and fossil Nitellopsis (Charophyta) in relationship to new finds from Morocca. J. of Biogeography 29 (12): 1703-1711.

U. S. DEPARTMENT OF THE INTERIOR, U. S. GEOLOGICAL SURVEY. 2016. Nonindigenous Aquatic Species Database, Gainesville, Florida. Nitellopsis obtusa. URL:nas.er.usgs.gov.

WISCONSIN DEPARTMENT OF NATURAL RESOURCES (WI DNR). 2014. Local effort to manage recently discovered invasive algae in southeast Wisconsin. Wisconsin Department of Natural Resources. Madison, WI.

WISCONSIN DEPARTMENT OF NATURAL RESOURCES (WI DNR). 2015. Aquatic invasive species by waterbody. Wisconsin Department of Natural Resources. Madison, WI.


This ssw power point presentation may be viewed on the Wawasee Area Conservancy Foundation Website at www.wacf.com

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