Lemna turionifera — turion duckweed
![Thalli: Lemna turionifera. ~ By Robert Freckmann. ~ Copyright © 2024 Robert Freckmann. ~ rfreckma[at]uwsp.edu ~ Robert W. Freckmann Herbarium, U. of Wisconsin-Stevens Point](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Araceae/lemna-turionifera-ta-rfreckmann.jpg)
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Facts
Turion duckweed is a widespread native duckweed. Its species name refers to the fact that it sometimes produces turions, vegetative plantlets that can disperse and go dormant for long periods. Its "leaves" (thalli) are often colored purple on their undersides and have tiny projections (papillae) along the midrib.
Habitat
Lacustrine (in lakes or ponds), riverine (in rivers or streams)
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
enlargeCharacteristics
- Habitat
- aquatic
- New England state
-
- Connecticut
- Massachusetts
- Rhode Island
- Vermont
- Roots
- there is approximately one root per thallus
- Thallus shape in cross-section
- the thallus is somewhat flattened on at least one side in cross-section
- Thallus length
- 1–4 mm
- Thallus shape
- the thallus is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
- Thallus dimensions
- 1–1.5
- Veins on upper surface
- 3
-
Flowers
- Scale surrounding flower
- no
- Stamen number
- 2
-
Fruits or seeds
- Fruit length
- 0.5–0.6 mm
- Seed surface ribbed
- the seed surface is nearly smooth
-
Growth form
- Root length
- Up to 150 mm
- Root number
- 1
- Root sheath winged at base
- no
- Roots
- there is approximately one root per thallus
- Roots perforating basal scale
- there is no basal scale on the plant
- Thallus dimensions
- 1–1.5
- Thallus edge
- the edge of the thallus is smooth (without teeth) near the tip
- Thallus length
- 1–4 mm
- Thallus shape
- the thallus is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
- Thallus shape in cross-section
- the thallus is somewhat flattened on at least one side in cross-section
- Thallus stalks
- the thallus has a stalk
- Thallus with red pigment
- yes
- Turions
-
- no
- yes
-
Leaves
- Papilla on thallus
- yes
- Veins on upper surface
- 3
-
Place
- Habitat
- aquatic
- New England state
-
- Connecticut
- Massachusetts
- Rhode Island
- Vermont
- Specific habitat
-
- in lakes or ponds
- in rivers or streams
Wetland status
Occurs only in wetlands. (Wetland indicator code: OBL)
In New England
Distribution
- Connecticut
- present
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- historical (S-rank: SH), H (code: H)
- Rhode Island
- extremely rare (S-rank: S1), concern (uncertain) (code: C*)
- Vermont
- historical (S-rank: SH)
From Flora Novae Angliae dichotomous key
5. Lemna turionifera Landolt NC
turion duckweed. CT, MA, RI, VT. Mesotrophic to eutrophic waters of lakes, rivers, beaver flowages, and pools.
Native to North America?
Yes
Sometimes confused with
- Lemna minor:
- turions never produced and parent plants usually green on lower surface (vs. L. turionifera, with small, rootless turions 0.8-1.6 mm in diameter sometimes produced and parent plants with red to purple coloration on lower surface).
- Lemna perpusilla:
- root sheath winged at base, roots up to 3.5 cm long, usually sharply pointed at apex, and thalli without anthocyanic pigment (vs. L. turionifera, with the root sheath not winged at base, roots to 15 cm long, frequently longer than 3.5 cm, rounded at apex, and thalli usually with anthocyanic pigment).