Brasenia schreberi - J.F. Gmel.
Other Common Names: watershield
Taxonomic Status: Accepted
Related ITIS Name(s): Brasenia schreberi J.F. Gmel. (TSN 18370)
French Common Names: brasÚnie de Schreber
Unique Identifier: ELEMENT_GLOBAL.2.130243
Element Code: PDCAB01010
Informal Taxonomy: Plants, Vascular - Flowering Plants - Other flowering plants
Kingdom Phylum Class Order Family Genus
Plantae Anthophyta Dicotyledoneae Nymphaeales Cabombaceae Brasenia
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Concept Reference
Concept Reference: Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Concept Reference Code: B94KAR01HQUS
Name Used in Concept Reference: Brasenia schreberi
Conservation Status

NatureServe Status

Global Status: G5
Global Status Last Reviewed: 14Jul2015
Global Status Last Changed: 16Feb1984
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Nation: United States
National Status: N5
Nation: Canada
National Status: N5 (14Jul2015)

U.S. & Canada State/Province Status
United States Alabama (SNR), Alaska (S1), Arkansas (SNR), California (S3), Connecticut (SNR), Delaware (S4), District of Columbia (SNR), Florida (SNR), Georgia (SNR), Idaho (SNR), Illinois (S1S2), Indiana (SNR), Iowa (S2), Kansas (SNR), Kentucky (S3S4), Louisiana (SNR), Maine (SNR), Maryland (S4), Massachusetts (SNR), Michigan (SNR), Minnesota (SNR), Mississippi (SNR), Missouri (SNR), Montana (S1S2), Nebraska (S2), New Hampshire (SNR), New Jersey (S4), New York (S5), North Carolina (S3S4), Ohio (SNR), Oklahoma (S1), Oregon (SNR), Pennsylvania (SNR), Rhode Island (SNR), South Carolina (SNR), South Dakota (SNR), Tennessee (SNR), Texas (SNR), Vermont (SNR), Virginia (S5), Washington (SNR), West Virginia (S4), Wisconsin (SNR)
Canada Alberta (S1), British Columbia (S5), Manitoba (S2), New Brunswick (S4), Newfoundland Island (S1), Nova Scotia (S5), Ontario (S5), Prince Edward Island (S1), Quebec (S4S5)

Other Statuses

NatureServe Global Conservation Status Factors

Range Extent Comments: Most of North America, widespread in other parts of the world except Europe. Sparse.

Other NatureServe Conservation Status Information

Global Range: Most of North America, widespread in other parts of the world except Europe. Sparse.

U.S. States and Canadian Provinces
Color legend for Distribution Map

U.S. & Canada State/Province Distribution
United States AK, AL, AR, CA, CT, DC, DE, FL, GA, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, NE, NH, NJ, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, VA, VT, WA, WI, WV
Canada AB, BC, MB, NB, NF, NS, ON, PE, QC

Range Map
No map available.

U.S. Distribution by County Help
State County Name (FIPS Code)
AK Ketchikan Gateway (02130)*
CA Butte (06007)*, El Dorado (06017), Fresno (06019), Glenn (06021)*, Lake (06033), Lassen (06035), Mendocino (06045), Plumas (06063), Sacramento (06067)*, San Joaquin (06077), Shasta (06089), Siskiyou (06093)*, Sutter (06101)*, Tehama (06103), Tulare (06107)*, Tuolumne (06109)
DE Sussex (10005)
IA Allamakee (19005)*, Black Hawk (19013), Buchanan (19019), Butler (19023), Clinton (19045), Hamilton (19079)*, Hancock (19081)*, Johnson (19103), Linn (19113), Muscatine (19139), Winnebagao (19189)*, Worth (19195)
MT Flathead (30029), Lake (30047), Lincoln (30053), Missoula (30063)
NE Boone (31011), Garfield (31071), Holt (31089), Loup (31115), Rock (31149), Wheeler (31183)
OK Atoka (40005), Cherokee (40021), Choctaw (40023), LeFlore (40079), McCurtain (40089), Nowata (40105), Pittsburg (40121), Pushmataha (40127)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
02 Broadkill-Smyrna (02040207)+, Chincoteague (02040303)+
07 Upper Iowa (07060002)+*, Upper Wapsipinicon (07080102)+, Lower Wapsipinicon (07080103)+, South Skunk (07080105)+*, Shell Rock (07080202)+, Winnebago (07080203)+*, West Fork Cedar (07080204)+, Middle Cedar (07080205)+, Lower Cedar (07080206)+, Middle Iowa (07080208)+*
10 Calamus (10210008)+, Loup (10210009)+, Cedar (10210010)+, Upper Elkhorn (10220001)+
11 Middle Verdigris (11070103)+, Lower Canadian (11090204)+, Illinois (11110103)+, Poteau (11110105)+, Muddy Boggy (11140103)+, Clear Boggy (11140104)+, Kiamichi (11140105)+, Pecan-Waterhole (11140106)+, Upper Little (11140107)+, Lower Little (11140109)+
16 Lake Tahoe (16050101)+
17 Upper Kootenai (17010101)+, Fisher (17010102)+, Yaak (17010103)+, Blackfoot (17010203)+, Flathead Lake (17010208)+, Stillwater (17010210)+, Swan (17010211)+
18 Upper Eel (18010103)+, Middle Fork Eel (18010104)+*, South Fork Eel (18010106)+*, Big-Navarro-Garcia (18010108)+, Russian (18010110)+*, Butte (18010205)+*, Lower Pit (18020003)+, Upper Cache (18020116)+, North Fork Feather (18020121)+, East Branch North Fork Feather (18020122)+, South Fork American (18020129)+, Big Chico Creek-Sacramento River (18020157)+, Butte Creek (18020158)+*, Upper Kern (18030001)+*, San Joaquin Delta (18040003)+, Upper San Joaquin (18040006)+, Upper Tuolumne (18040009)+, Upper Mokelumne (18040012)+*, Honey-Eagle Lakes (18080003)+
19 Ketchikan (19010102)+*
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
General Description: Watershield is a rhizomatous perennial aquatic herb with branches which rise through the water, floating leafblades (lily pads), and emergent flowers. The leaves have long petioles attached alternately to the branches and centrally to the undersides of the floating leaf blades. The broadly elliptic to oval leaf blades are 4-12 cm long and 3-8 cm wide. Solitary flowers are held just above the water on long peduncles. The flowers usually have 3 sepals and 3 petals which are similar, translucent reddish-purple colored, linear to lance-shaped, and 1-1.5 cm long. There are 4-14 pistils and 12-36 purplish stamens which are about the same length as the petals and sepals. The leathery, beaked fruits are 6-8 mm long and mature underwater.
Diagnostic Characteristics: Distinguished from other water lilies (NUPHAR, NYMPHAEA) by its relatively small, purplish, many pistilled flowers and by its relatively small, truly peltate (with petiole attached to the center of the blade) leaves.
Economic Attributes Not yet assessed
Management Summary Not yet assessed
Population/Occurrence Delineation Not yet assessed
Population/Occurrence Viability
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
Element Ecology & Life History Edition Date: 08Oct1994
Element Ecology & Life History Author(s): JM

Botanical data developed by NatureServe and its network of natural heritage programs (see Local Programs), The North Carolina Botanical Garden, and other contributors and cooperators (see Sources).

  • Flora of North America Editorial Committee. 1997. Flora of North America north of Mexico. Vol. 3. Magnoliophyta: Magnoliidae and Hamamelidae. Oxford Univ. Press, New York. xxiii + 590 pp.

  • Frodge, J. D., G. L. Thomas, and G. B. Pauley. 1990. Effects of canopy formation by floating and submergent aquatic macrophytes on the water quality of two shallow Pacific Northwest lakes. Aquatic Botany 38(2):231-248.

  • Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

  • Meades, S.J. & Hay, S.G; Brouillet, L. 2000. Annotated Checklist of Vascular Plants of Newfoundland and Labrador. Memorial University Botanical Gardens, St John's NF. 237pp.

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