Aquatic Plants Assessment Summary Table

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Species	Common Name	P¹	R²	W³	NR⁴	ii⁵	SAG Final Recommended Classification	SAG comments (bold is recommended, italics are comments from DNR staff)⁶	Council Recommendation 10-17-07
¹ number of prohibited votes, ² number of restricted votes, ³ number of caution votes, ⁴ number of non-restricted votes, ⁵ number of insufficient information, ⁶ part of the recommendation, the non-bold text comment from the group
AQUATIC PLANTS & ALGAE
SAG Members - Robert Dahl, DATCP; Tim Hoyman, WAL; Shawn Wenzel, Aquatic Innovators, LLC; Laura Herman, UWSP; Dr. Robert Freckmann, UWSP Freckmann Herbarium; John Skogerboe, USACOE; Kristy Maki, Sawyer County; Phil Moy, Sea Grant (not present); Bill Ratajczyk, Applied Biochemists; Tony Kuchma, Oneida Tribe; Susan Lehnhardt, Applied Ecological Services, LLC; Facilitator - Bob Korth (UWSP Lakes Program); DNR Leader - Dr. Jennifer Hauxwell, Science Services; Meeting Date - 9-26-07 Other Attendees - Kelly Kearns, DNR; Erin Hennegar (UWSP Lakes Program), Alison Mikulyuk (DNR), Michelle Nault (DNR)
Azolla pinata	Mosquito fern, Water velvet			10			CAUTION	1- How will spores overwinter? 2- Will not overwinter in WI. high botanical interest because of unique life cycle. 7- Will be more problematic given warm water discharge. 5-Will be more problematic in acidic systems. 4-Unlikely habitat in WI.	CAUTION
Butomus umbellatus	Flowering rush	1	9				RESTRICTED	1- Climate 6- Suggests integration of management techniques. 8&10-Some commercial use. 2-Now that we can recognize this plant vegetatively, it appears to be more widespread than we thought.	RESTRICTED
Cabomba caroliniana	Fanwort	5	4	1			PROHIBITED	1- May be restricted to Southern Wisconsin; climate modeling suggests survival in MN; small expt had survival of a few plants in MN. 2-Does not believe it will overwinter. 3-Fairly resistant to herbicides; nationwide distribution; has potential to survive in WI. 10- Concerned with financial impact of Prohibited rating. 6-Survives well in S. IN. 7-Seeds readily germinate in Washington.	PROHIBITED
Callitriche stagnalis	Pond water starwort		3	7			CAUTION	6- Establishment potential seems very low. 3-Easy to control. 2-Very difficult to distinguish from native Callitriche spp.	CAUTION
Crassula helmsii	Australian swamp stonecrop, New Zealand pygmyweed	10					PROHIBITED	Group comment - This is the only unanimous species of the 27 for prohibited with no discussion needed. 6-UK only permits 2 herbicides, integrated treatments and additional herbicides may be effective.	PROHIBITED
Didymosphenia geminata	Didymo, Rock snot	2	7	1			RESTRICTED	Group Comment: Would prohibit this species if we knew of a practical control measure. 1,2,3-Not aware of anything to be done outside of preventing spread once it is introduced. 4-We should prohibit. This species is unique in that it infests high-quality, oligotrophic, high clarity habitats and threatens some of our most valuable natural resources. 6-May be major problem in restored trout streams, need more science on eradication (look to Clemson for information). JH-Consistency suggests Prohibited rating (based on current distribution - not yet in WI).	PROHIBITED- decided on prohibited, even though difficult to manage
Egeria densa	Brazillian waterweed	6	3	1			PROHIBITED	Group comment: Prohibited rating approved as long as there is exemption granted for educational uses (for this plant only). 2-Valuable for high school science experiments, and not aware of a suitable replacement model. Has been used for a very long time and that it has not yet established may indicate its inability to do so. 3-Limited control measures, only options are non-selective. Has established and overwintered as far north as Minneapolis. 1-Model predicts marginal populations in Minnesota. 6-Has dealt with this in other northern states, very invasive. JH-Suggest Prohibited classification without exemption based on recent discovery in MN, Powderhorn Lake, definite overwintering based on broad distribution.	PROHIBITED- permit for education, details to be worked out later
Eichhornia crassipes	Water hyacinth		3	6	1		CAUTION	10- Heavily used in water gardening. Eradication of small populations is easy, plant does not overwinter. 6,7,8,9-Concern about establishment in warm-water areas. 3-Could be invasive as an annual. 2-Concerned about heavy opposition from the public if regulated.	CAUTION
Hydrilla verticillata	Hydrilla	10					PROHIBITED	9-Discovered recently in artificially-planted pond. Went from 1 plant to 3/4acre in two years. 6-Overwinters well, highly invasive. 3-Wherever it is found should start aggressive eradication program.	PROHIBITED
Hydrocharis morsus-ranae	European frog-bit	8	2				PROHIBITED	2-Good opportunity to catch this species before it gets here, before it catches on in the water garden industry.	PROHIBITED
Hygrophila polysperma	East Indian Hygrophila, Indian swampweed			10			CAUTION	3-Could do a lot of damage if it grew here, but that's unlikely. JH - consider Prohibited classification (insufficient information, so must make judgement call; Prohibited in MN).	CAUTION
Ipomoea aquatica	Water spinach, Swamp morning-glory			7	3		CAUTION	9-Found in many grocery stores. 2-Potential to seed in a growing season, overwinter as seed.	CAUTION
Lagarosiphon major	Oxygen-weed, African elodea, African waterweed	5	3	2			PROHIBITED	2-Unlikely this species will be introduced. 3-Adapted to our climate, but no source population. 5-Would be a good idea to prevent establishment since it isn't nearby yet. 7-May be introduced in shipping (wrapping fish in plants to keep them moist) 8-Damage potential is quite high. If we are considering resources available for regulation, restrict, if just damage potential, prohibit.	PROHIBITED
Landoltia punctata	Dotted duckweed			10			CAUTION	2- transported by a variety of animals, if not already here, it is likely that the plant cannot survive. 7-ii re: its potential to overwinter. JH - consider Prohibited classification (insufficient information, so must make judgement call - lower priority than others).	CAUTION
Limnophila sessiliflora	Limnophila, Asian marshweed			9		1	CAUTION	Group comment: need more information on how long to seed maturity.	CAUTION
Marsilea quadrifolia	Water shamrock, European waterclover	2	2	6			CAUTION	Group Comment: Less information available on this species - resulted in quite a few ii ratings for categories. 4- in IL, plant grows in small isolated groups in cool, strip-mined ponds; perhaps has unique growing needs. 2-Does not overwinter but does well in greenhouse; JH - consider Prohibited classification (insufficient information, so must make judgement call).	6 prohibited, 4 caution and take back to SAG then to WCIS
Myriophyllum aquaticum	Parrot feather	5	2	3			PROHIBITED	A lot of discussion among group regarding rating. There are strong concerns about rating it as Prohibited because of plant's importance to water plant trade and the popularity of the plant with the public . Investigate red-stemmed versus regular type. 2- Rarely overwinters. 3- Plant will grow in littoral zone where there is the most species diversity. 10-Popular plant in water garden industry. 6-More investment with control and research lately which speaks to growing nuisance and concern; plants distribution looks familiar to how hydrilla spread across country; is now surviving winters in NY. 1-Concerns with this species' ability to quickly evolve more tolerant forms. 7-Very good mosquito habitat, public may appreciate regulation. Reports of hardy overwintering in Madison by a master gardener.	PROHIBITED
Myriophyllum spicatum + hybrids	Eurasian watermilfoil + hybrid watermilfoil		10				RESTRICTED	Group Comment: Unknowns exist about the behaviour of the hybrid, but caution is warranted as most information indicates similarities. 2- Way too late to do anything about current status and distribution.	RESTRICTED
Najas minor	Brittle (Lesser, Bushy, Slender, Spiny, Minor) naiad, waternymph		7	2		1	RESTRICTED	10- Not used in water gardens. Questions about survivability. 9-need more information to give final designation. 7-Need more information. 2-Regulation will be difficult because this plant will be hard to recognize. JH-Consistency suggests Prohibited rating (based on current distribution - recently found in 1 lake in WI).	PROHIBITED
Nasturtium officinale / Rorippa nasturtium-aquaticum	Watercress			8	2		CAUTION	2-People love to use this plant in salads. 4- found large population of watercress that had likely reduced native plant populations. 10-Popular plant in water gardening industry.	CAUTION
Nymphoides peltata	Yellow floating heart	9		1			PROHIBITED	2-Nice garden plant, will it really establish? 3-In same pond as hydrilla (Marinette Cty.), had to really work to control. 10-Grows very quickly, helps clear water, must pull frequently to prevent from taking over. Important plant in water gardening industry. Does overwinter.	PROHIBITED
Ottelia alismoides	Ducklettuce			8	2		CAUTION	2- Critical question: can it mature to seed within one growing season? If it can, we may have something to worry about. JH - consider Prohibited classification (insufficient information, so must make judgement call); Prohibited in MN.	CAUTION
Pistia stratiotes	Water lettuce			9	1		CAUTION	10,7,2- Never any success in overwintering. JH - suggests Prohibited rating due to potential of re-emergence from seeds each year. Definite judgement call due to insufficient information on long-term ecological impacts in northern ecosystems. If it overwinters, could have major ecological impacts. However, used heavily in industry.	CAUTION
Potamogeton crispus	Curly-leaf pondweed		10				RESTRICTED	3-Need more info on the damage potential in oligo-mesotrophic lakes.	RESTRICTED
Salvinia spp	Salvinia species		2	8			CAUTION	2-Perpetually unsuccessful in overwintering. Very interesting plant, botanically speaking. 3-May be cold-limited even in Texas.	CAUTION
Stratoites aloides	Water soldiers				10		NON-RESTRICTED	Group Comment: Erroneously included on federal list not know to be a problem anywhere.	NON-RESTRICTED
Trapa natans	Water chestnut	10					PROHIBITED	6- Very invasive plant in the East.	PROHIBITED
SUMMARY: TOTAL SPECIES: 27 Prohibited = 9, Restricted = 5, Caution = 12, Non-Restricted = 1, ii = 0

Last Revised: Wednesday April 23 2008