Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Elodea nuttallii

free-flower waterweed, Nuttall's waterweed, western waterweed
Leaves

mostly in 3s, often recurved, linear to lanceolate, 4–15.5 × 0.9–1.7(–2.4) mm, margins folded.
Inflorescences

staminate spathes subglobose to ovoid, 2.2–4 mm;

peduncles abscissing in bud; pistillate spathes linear, 8.5–15 mm.
Flowers

unisexual; staminate flowers: stamens 9, pedicels briefly remaining attached following anthesis;

inner 3 filaments connate proximally, forming column;

anthers 1–1.4 mm;

pollen in tetrads; pistillate flowers: styles mostly 1.2–2 mm.
Seeds

fusiform, 4–4.6 mm, base with long hairs.
2n

= 48 (Britain).

Elodea nuttallii
Phenology Flowering summer.
Habitat Waters, mostly calcareous, of lakes and rivers
Elevation 50–1600 m (200–5200 ft)
Distribution
from FNA
AR; CA; CO; CT; DE; IA; ID; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; MT; NC; ND; NE; NH; NJ; NV; NY; OH; OK; OR; PA; RI; SD; TN; VA; VT; WA; WI; WV; WY; NB; ON; QC; Europe; Asia
[WildflowerSearch map]
[BONAP county map]
Discussion

I know of no instance in North America where Elodea nuttalli or E. canadensis is weedy. Both are weedy in Europe, and E. canadensis is weedy also in Australia and New Zealand.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Source FNA vol. 22.
Parent taxa Hydrocharitaceae > Elodea
Sibling taxa
E. bifoliata, E. canadensis
Synonyms Anacharis nuttallii
Name authority (Planchon) H. St. John: Rhodora 22:29. (1920)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Fabaceae, Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America, OregonFlora, UW Burke Herbarium

The species comparison tool is brought to you by:
Northwest Wildflowers