Manyflower Marshpennywort Hydrocotyle umbellata
Manyflower Marshpennywort is a perennial wildflower native to Canada, the lower 48 states, and Puerto Rico. It blooms Mar – Oct.
More about this plant
Hydrocotyle umbellata is an aquatic plant that thrives in wet, sandy habitat. It is known by several common names, including manyflower marshpennywort, dollarweed, water pennywort, and as acariçoba. It is native to North America and parts of South America. At the north of its range, in Canada, the species is only known from three lakes located in southwestern Nova Scotia. Most of the Canadian population is found within Kejimkujik National Park. In Brazil, acariçoba has applications in herbal medicine with purported anxiolytic, analgesic and anti-inflammatory properties. It can also be found growing as an introduced species and sometimes a noxious weed on other continents. It is an edible weed that can be used in salads or as a pot herb. In some parts of its native American range, manyflower marshpennywort is considered to be a species at risk, as well as in Canada, where water pennywort is listed as threatened federally and as endangered in Nova Scotia. Wikipedia →
Growing & care
USDA PLANTS · TRY- Hardiness
- ≥ zone 5 derived from its U.S. range
- Lifespan
- Perennial
- Foliage
- Broadleaf
- Flower colour
- White AI AI image-analysis of community-science photos (~87% expert agreement) — not a botanical record
Wildlife & pollinators
How pollinator value is scored →❧ Caterpillar hosts ~2 caterpillar species
Hydrocotyle supports ~2 caterpillar species.
Native butterfly & moth caterpillars are the base of the terrestrial food web — most songbirds rear their young almost entirely on them. As a host for native Lepidoptera this is a modest genus.
Recorded feeding on Hydrocotyle in North America, including:
✦ Bees 1 bee visitor
1 native & managed bee species is documented visiting Manyflower Marshpennywort :
Wildlife & visitors 3 birds · 1 nectaring
Open records of who else uses Manyflower Marshpennywort — a generalist food-web signal, kept separate from the keystone Ecological Value.
Recorded eaten by 3 birds species (fruit, seed, browse):
1 adult butterfly & moth species is recorded nectaring at its flowers:
Across 26 U.S. vegetation-survey plots that recorded Manyflower Marshpennywort, these catalog species turned up most often in the same plot — a real field co-occurrence signal, not a planting prescription.
Related plants
More Hydrocotyle →
How we know this (3) Methods & honest limits
A recorded categorical fact: each species is tagged C3 (standard), C4 (heat/water-efficient) or CAM (succulent, night-time CO₂ uptake) — or a facultative combination. We only show a trait card for the noteworthy C4/CAM cases; C3 is the unremarkable majority, kept in the data but not surfaced as a card.
We take the plant’s U.S. county range and look up each county’s long-term climate, then summarise: native rainfall = the median annual rainfall across its counties; heat tolerance = the warm end (90th percentile) of average temperature across its range (mirroring how our cold-hardiness floor uses an extreme). Counties + medians blunt the roadside/observer bias that makes point-level climate unreliable. Needs at least five placeable counties.
Honest limits: A realized, sampling-biased niche (where it has been recorded, not its physiological optimum), and county climate is coarse — large Western counties span deserts and mountains. Derived guide, never a measured fact.
McKenzie et al. assigned each species a flower colour with a GPT-4V vision model over iNaturalist photos. We use the confident tier plus a separately-labelled lower-confidence top-up (mostly inconspicuous green/brown flowers), and render it as a small tint — never as an asserted fact, and kept out of the written synopsis.
Honest limits: AI image inference (~87% expert agreement on the confident tier); a decorative, confidence-tiered indicator, not a measured trait.
Sources for this entry (25) Open & cited
Cite this page Open data, please attribute
PlantKey’s data is open under CC BY-SA 4.0 — free to reuse and adapt, with attribution and the same licence. Photos keep their own per-image licence + credit (see Sources above).
Loading…
BibTeX
Loading…