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A Forager’s Year

No. 159

Broadleaf arrowhead

Sagittaria latifolia

duck potato, wapato

Roots, bulbs & tubers tubers (cooked)

Drawing: Britton & Brown, Illustrated Flora (1913)

Find
Common in the right habitat
Effort
Real work
ID risk
Careful
Origin
native
Safety marks
  • Deadly lookalike
  • Cook first
  • Spray risk
Uses
  • Cooked vegetable / soup
  • Baking & desserts

Season

  1. Jan
  2. Feb
  3. Mar
  4. Apr
  5. May
  6. Jun
  7. Jul
  8. Aug
  9. Sep
  10. Oct
  11. Nov
  12. Dec

in season peak

Picking: No park we checked allows it. Anywhere else, ask whoever owns or runs the land. See Where you may pick.

What these mean

Find

1 Everywhere · 2 Common in the right habitat · 3 Patchy · 4 Elusive. This is about how much there is, not whether you may pick it. It is based on iNaturalist sightings within 25 km (about 15 miles) of downtown DC, counted on October 3, 2026. The four rules that each plant’s “Find” reason refers to: (A) the estimate is the confirmed sightings, plus the unconfirmed ones (scaled down where the plant has lookalikes in its genus), plus the sightings marked as planted; (B) the tier by estimate: 1,500 or more is tier 1, 250–1,499 tier 2, 50–249 tier 3, under 50 tier 4; (C) tier 1, Everywhere, also needs a source saying the plant is common in lawns, sidewalks, yards or gardens, vacant lots or towns, or at least one DC street tree of it per km of sidewalk, otherwise it is tier 2; (D) if a reliable source says the plant is rare in this region, or that wild plants rarely bear the harvest, only planted sightings count. iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.

Effort

1 Grab & eat · 2 Quick kitchen prep (under about 30 minutes) · 3 Real work (hours, or cooking needed for safety) · 4 Project (days or equipment). Scored on the simplest worthwhile use; each plant’s page says why.

ID risk

How hard it is to harvest safely. Beginner: no dangerous lookalike, and the edible part is not easily confused with a toxic part. Careful: a toxic lookalike, or toxic parts that end up in the harvest unless removed (for example elderberry stems, unripe ground cherries), or other parts of the plant rated medium-or-higher toxicity, with reliable features to separate them. Expert only: a potentially deadly lookalike that is hard to separate, or (for not-recommended harvests like pokeweed) a plant whose safe preparation can’t be guaranteed. Toxic parts that are obviously separate and thrown away anyway (pits, seeds, skins) don’t raise it; the Toxic parts mark carries that warning.

Native or not, and the invader stars

Origin is where the plant comes from: native, non-native, or mixed (the harvest covers both). The stars rate plants on invasive plant lists: ★★★ Virginia DCR “High” or Maryland prohibited invasive · ★★ Virginia “Medium” · ★ Virginia “Low” · ☆ listed only by the Maryland Invasive Species Council or the Mid-Atlantic Plant Invaders guide (advisory) · no stars: native or not listed.

Safety marks and flags

Deadly lookalike / Toxic lookalike: a cited source names a lookalike of that danger, recorded near DC (an iNaturalist sighting within 25 km, a DC street tree, or a Smithsonian listing for DC) and looking like the part you eat. Other lookalikes are still listed, marked “not recorded near DC” or as not looking like the part you eat. Deadly means a source says eating it may be fatal or calls it deadly, or NC State rates it high severity with life-threatening symptoms (sources sometimes disagree; for example Virginia creeper). Each plant’s Lookalikes list says how to tell them apart; “harmless (may be edible)” lookalikes are listed so you know a mix-up isn’t dangerous. Cook first: cooking is needed for safety (for daylilies it is a precaution, not a sourced requirement). Eat in moderation: a source says to limit quantity or frequency (for example oxalates in sorrels and dock, ginkgotoxin, safrole). Spray risk: a source says the plant is commonly treated with herbicide in parks or lawns (invasive control, lawn weeds) or, for ginkgo, sprayed to stop fruiting. Contamination: a source says the plant concentrates pollutants. Each plant’s Safety flags list gives the details and sources.

Seasons

Start, peak and end are given in thirds of a month: early, mid or late. A plant counts as in season for a month if it is in season at any point in that month. Some greens and roots have a second window, in spring or fall; their page shows each window. A season that runs across New Year is shown as one window.

What it looks like

The starchy tubers of broadleaf arrowhead, a native water plant with arrow-shaped leaves and white, three-petaled flowers in whorls of three (NC State). The tubers are chestnut-size and form in the mud around the plant like numbers on a clock (Eat The Weeds); they are white or bluish (USDA) and taste similar to potatoes or chestnuts (NC State). A single plant can yield up to 40 tubers a year (USDA). Raw tubers are bitter, and cooking makes them less so (Mississippi State University Extension; Eat The Weeds). Native Americans ate the starchy tubers (NC State), and Lewis and Clark considered them equal to the potato (USDA).

Safety

No part of broadleaf arrowhead is listed as poisonous (NC State). Deadly lookalike: arrow arum (tuckahoe), which grows in the same marshes with similar arrow-shaped leaves; its calcium oxalate affects the mouth and digestive tract unless it is thoroughly cooked or dried (NC State; Mississippi State University Extension), and a raw root burns the mouth (Eat The Weeds). Maryland’s state archaeology museum (Jefferson Patterson Park & Museum) says swallowing arrow arum can be fatal. Arrowhead leaf veins all spread from the base of the leaf, one to each lobe (NC State; USDA), while arrow arum leaves have prominent veins down the middle and along the edge (Chesapeake Bay Program). Arrowhead tubers are chestnut-size and lie in the mud around the plant, while arrow arum grows from a thick rootstock a foot or more down (Eat The Weeds). Eat The Weeds says the two look alike when not in flower, so confirm a stand by its white, three-petaled flowers in summer before digging in fall. Fernald & Kinsey (1958) also name wild calla, a toxic plant with heart-shaped leaves, a white spathe and red berries (NC State), but it is not recorded near DC. Pickerelweed, which NC State says is often confused with arrowhead, has heart-shaped leaves and spikes of blue flowers (Chesapeake Bay Program; NC State); NC State lists no poison for it, but its root is not described as food. Cook the tubers: CDC says people most often catch the Fasciola liver fluke by eating raw watercress or other freshwater plants, and raw tubers are bitter (Mississippi State University Extension), although NC State says they may be eaten raw. Broadleaf arrowhead takes up metals from the mud and water it grows in (USDA; Restoration Ecology, 1993), so gather only from clean, unpolluted water (Eat The Weeds; Virginia Cooperative Extension). Virginia’s Department of Wildlife Resources and Mississippi State University Extension list herbicides for treating arrowhead in ponds, so ask the owner about spraying before picking. Virginia Cooperative Extension advises never harvesting aquatic plants alone and wearing boots or waders and a life vest.

Lookalikes

Safety flags

Safety marks and flags: what this means

Deadly lookalike / Toxic lookalike: a cited source names a lookalike of that danger, recorded near DC (an iNaturalist sighting within 25 km, a DC street tree, or a Smithsonian listing for DC) and looking like the part you eat. Other lookalikes are still listed, marked “not recorded near DC” or as not looking like the part you eat. Deadly means a source says eating it may be fatal or calls it deadly, or NC State rates it high severity with life-threatening symptoms (sources sometimes disagree; for example Virginia creeper). Each plant’s Lookalikes list says how to tell them apart; “harmless (may be edible)” lookalikes are listed so you know a mix-up isn’t dangerous. Cook first: cooking is needed for safety (for daylilies it is a precaution, not a sourced requirement). Eat in moderation: a source says to limit quantity or frequency (for example oxalates in sorrels and dock, ginkgotoxin, safrole). Spray risk: a source says the plant is commonly treated with herbicide in parks or lawns (invasive control, lawn weeds) or, for ginkgo, sprayed to stop fruiting. Contamination: a source says the plant concentrates pollutants. Each plant’s Safety flags list gives the details and sources.

ID risk
Careful
Why
Deadly arrow arum grows in the same marshes with similar arrow-shaped leaves (NC State; Mississippi State University Extension; Maryland’s state archaeology museum), and Eat The Weeds says the two look alike when not in flower. Arrowhead leaf veins all spread from the base of the leaf, one to each lobe (NC State; USDA), while arrow arum has prominent veins down the middle and along the edge (Chesapeake Bay Program); arrowhead has white three-petaled flowers, arrow arum a flower spike in a green sheath (NC State). Arrowhead tubers are chestnut-size and lie around the plant, while arrow arum grows from a thick rootstock a foot or more down (Eat The Weeds), so confirm a stand in flower before digging in fall. Wild calla, which Fernald & Kinsey (1958) pair with arrowhead, is not recorded near DC.
Soil risk
higher
ID risk: what this means

How hard it is to harvest safely. Beginner: no dangerous lookalike, and the edible part is not easily confused with a toxic part. Careful: a toxic lookalike, or toxic parts that end up in the harvest unless removed (for example elderberry stems, unripe ground cherries), or other parts of the plant rated medium-or-higher toxicity, with reliable features to separate them. Expert only: a potentially deadly lookalike that is hard to separate, or (for not-recommended harvests like pokeweed) a plant whose safe preparation can’t be guaranteed. Toxic parts that are obviously separate and thrown away anyway (pits, seeds, skins) don’t raise it; the Toxic parts mark carries that warning.

Soil risk: what this means

Based on the part you eat, following the urban-soil lead guidance on the Field safety page: higher for greens, shoots and roots; moderate for flowers; low for fruit, nuts and sap.

Field safety for every outing (poison ivy, ticks, soil, and more)

When to pick

Starts
mid Sep
Peak
mid Oct–late Nov
Ends
late Mar

Before the leaves die back in mid fall, the plant moves its stored food into the tubers (USDA). Traditionally the harvest was made in late summer as the stems and leaves were dying (USDA), Eat The Weeds says the tubers are best in fall, and USDA says tubers can be collected while the plants are dormant, in fall, winter and early spring. No source gives dates for the DC area, so all three boundaries are estimates.

How the dates were worked out

Every start, peak and end was re-checked in October 2026. “Sourced” means a source opened during the check states that timing for the DC or Mid-Atlantic area. “Estimated” means no source states it exactly; the reason, the evidence and the source links are under “How the dates were worked out” on each plant’s page. Peaks are often estimated, because few sources name a peak. iNaturalist evidence means research-grade sightings near DC, by month, of the plant at that stage (for example, in fruit). iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.

Season basis: estimated: start, peak, end

Start

estimated: No source dates the start for the DC area; mid September is late summer here, when the leaves begin to die back and iNaturalist sightings start to fall, as the tubers fill with the food stored before the mid-fall die-back.

Peak

estimated: No source names a best month for the DC area; mid October to late November is the fall that Eat The Weeds calls best, after the mid-fall die-back has filled the tubers.

End

estimated: No source gives an end date; late March is the early-spring end of the dormant season USDA gives, before new leaves come up.

Evidence

start: USDA plant guide: 'The harvest of arrowhead was usually made in late summer as the stems and leaves were dying'. USDA fact sheet: 'by mid fall the emergent plant parts annually die back to the root crown. Prior to the annual die back, nutrients and carbohydrates are translocated to subterranean tubers'. iNaturalist: research-grade DC-area sightings fall from 221 in September to 23 in October. | peak: Eat The Weeds: 'best in fall'. USDA fact sheet: 'by mid fall the emergent plant parts annually die back to the root crown'. | end: USDA plant guide: 'Potatoes should be collected and planted when plants are dormant, in the fall, winter and early spring.' iNaturalist: the first research-grade leaves of the year are logged in late March and April (1 in March, 8 in April).

Where to look

Shallow water of marshes, ponds and slow streams; Huntley Meadows and Kenilworth Aquatic Gardens have by far the most logged plants, followed by Four Mile Run, Theodore Roosevelt Island and the C&O Canal, but all of these ban picking, so pick or dig only on private land with the owner’s permission, in clean water.

Habitats
disturbed ground & waste places, floodplain & stream-valley forest, wetlands, marshes & pond edges
Habitats: what this means

Listed where the plant’s own sources place it in that habitat. “Disturbed ground & waste places” means a cited source places it on disturbed areas, sites, soil or ground, on waste places or waste ground, on construction or abandoned building sites (old home sites count), on rubble or in strip mines. When the source gives examples of the disturbed places, at least one example must be of that kind. Examples that do not count: natural or forestry disturbance (treefall gaps, fire, windthrow, flood scour, old riverbanks and creeks, clear-cuts); roadsides, railroads and rights-of-way; and abandoned fields, pastures and farmland, which are “Old fields & meadows”. “Vacant lots” only where a source says vacant or empty lots.

Most-logged places

None of the most-logged places allows picking.

No picking here (5 places)
  • Huntley Meadows Park

    117 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: Fairfax County parks ban removing any plant part without written permission.

  • Kenilworth Park & Aquatic Gardens

    105 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: Kenilworth is a NACE site that is not on the compendium’s list of gathering areas.

  • Four Mile Run stream valley (Arlington/Alexandria)

    19 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: Arlington County park rules (flora shall not be removed or disturbed) and Alexandria’s permit rule both apply.

  • Theodore Roosevelt Island

    15 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: GW Memorial Parkway sites (incl. Great Falls VA, Theodore Roosevelt Island, Dyke Marsh) designate nothing for gathering.

  • C&O Canal NHP (towpath, Georgetown to Great Falls MD and beyond)

    13 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: the C&O Canal compendium covers only edible fruits, nuts, berries and mushrooms, and NPS parks can never designate leaves, flowers, roots or sap. Of these, 3 are at Carderock.

Most-logged places: what this means

The places with the most research-grade iNaturalist sightings within 25 km of downtown DC (re-counted in October 2026 over every named place, campuses, condominiums and private grounds included), each marked legal to pick or not. A sighting inside several named places counts once, for the smallest of them, but a sighting inside a National Park Service park never counts for a private, campus or unchecked place. iNaturalist shows where people walk and log plants, not true abundance. Private campuses, condominiums, museums, estates and utility land (Pepco’s power-line land near Sligo Creek) are marked “no” (pick only with the owner’s permission); public university campuses, city parks and other places whose picking rules were not checked (county stormwater land, the U.S. Capitol Grounds, Greenbelt’s North Woods, federal facilities such as the National Zoo) are “unknown”. A place needs at least 2 sightings, so plants with very few sightings have no places. At-risk plants (butternut, nannyberry, American chestnut, ramps, riverbank goldenrod) get places like every other plant; each page says why the plant is at risk and gives any advice its sources give. For some places, mostly Rock Creek Park, the iNaturalist map shows more sightings than the count here, because a map link cannot leave out exactly the sightings credited to another place. iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.

Ways to use it

  • boiled or roasted for about half an hour, then used like potatoes (Eat The Weeds)
  • baked in embers, boiled or roasted, then skinned and eaten whole or mashed (USDA)
  • dried and ground into powder for soups and bread (Eat The Weeds)
  • cooked tubers added to a stew of jerky, hominy and onion (Eat The Weeds recipe)
  • harvest by shuffling around the plants with your feet, or working the mud with a small rake, hoe or pitchfork, so the tubers float up (Eat The Weeds; USDA)
  • harvest tip: cut off the sprout before cooking and peel the tubers after cooking (Eat The Weeds)

Keeping

Keep cold and moist and use within a few weeks, or dry them and grind them into powder.

Use within
weeks
Keeps fresh
Keep the tubers cold and moist, for example in perforated plastic bags in the refrigerator (general guidance for root vegetables; University of Minnesota). USDA, writing about tubers kept for planting, says to keep them moist and cool and store them in peat moss.
Keeping basis
general guidance for its type

Ways to keep it

  • Dry as researched: dry/dehydrate; canning: n/a (not shelf-canned)

    Eat The Weeds: the tubers can be dried and ground into powder for soups and bread. USDA: some tubers were dried after roasting and stored for winter use, and the Chippewa strung them and hung them to dry. Store dried foods airtight in a cool, dry, dark place; NCHFP gives 4 months to 1 year for dried foods.

  • Store whole as researched: root cellar; canning: n/a (not shelf-canned)

    University of Minnesota: root crops want cold, moist storage (32–40°F, about 95% humidity); perforated plastic bags in the fridge give this for a moderate time, and root cellars give it longer (general guidance for root vegetables).

Canning: what this means

Shelf-stable canning, three levels. Lab-tested: a lab-tested recipe from the National Center for Home Food Preservation (NCHFP) or Oregon State covers this fruit and product, or a generic recipe for its kind (the line says so, for example chokeberry). Extension recipe: a published Extension recipe (University of Alaska Fairbanks, written for Alaska species; University of Maine’s dandelion jelly), or a process that is safe only with a pH meter; follow it exactly, never improvise. No tested recipe: refrigerate or freeze, don’t can. “Hot-bottled syrup” = maple and walnut syrup, which keep when bottled hot at full syrup density. The Canning line names the exact product each source covers, for example “whole berries” or “juice”; a product not named there (such as juice from a berry with only a whole-berry recipe) has no tested recipe.

Keeping basis: what this means

“Specific to this plant” or “general guidance for its type” (for example NCHFP guidance for leafy greens applied to a wild green).

Nutrition

Not researched: in October 2026, only the calendar’s plants of the month and chicory leaves were researched.

Native or not

Origin
native
Native range
Canada, the central and eastern United States, Cuba, and western South America (per NC State)
Virginia invasive rank
not listed
Maryland invasive status
not listed
Native or not, and the invader stars: what this means

Origin is where the plant comes from: native, non-native, or mixed (the harvest covers both). The stars rate plants on invasive plant lists: ★★★ Virginia DCR “High” or Maryland prohibited invasive · ★★ Virginia “Medium” · ★ Virginia “Low” · ☆ listed only by the Maryland Invasive Species Council or the Mid-Atlantic Plant Invaders guide (advisory) · no stars: native or not listed.

Virginia DCR, Virginia Invasive Plant Species List (effective September 2024), verbatim: "Under the DCR Invasive Species Assessment Protocol, approved by the Virginia Invasive Species Working Group, January 2024, species were ranked as exhibiting high, medium or low levels of invasiveness based on their threat to natural communities and native species. Invasiveness rank is higher for species that: • Alter ecosystem processes, such as succession, hydrology or fire regime. • Are capable of invading undisturbed natural communities. • Cause substantial impacts on rare or vulnerable species or natural communities or high-quality examples of more common communities. • Are found widely distributed and generally abundant where present. • Disperse readily to new areas. • Are difficult to control." The list also states: "The list is for educational purposes only and has no regulatory authority."

Maryland Department of Agriculture, Maryland Prohibited Invasive Plant Law and Regulations page, verbatim: "Plants on the Maryland Prohibited Invasive Plant List may not be added to stock after the effective date and should not be sold after their phase-out period ends."

No official DC invasive plant list was found.

How the ratings were set

Find
Common in the right habitat Estimate 732 = 476 research-grade iNaturalist sightings within 25 km + 256 needs-ID sightings counted at 97% (476 of the 493 research-grade Sagittaria sightings here are broadleaf arrowhead) + 9 'cultivated' (planted) sightings (rule A); that is tier 2 by count (rule B). Final tier 2.
Effort
Real work Wade into the shallows and loosen the tubers from the mud with your feet or a small rake so they float up, cut off the sprouts, boil or roast them about half an hour and peel them; drying and grinding them into powder is also a 3.
Find: what this means

1 Everywhere · 2 Common in the right habitat · 3 Patchy · 4 Elusive. This is about how much there is, not whether you may pick it. It is based on iNaturalist sightings within 25 km (about 15 miles) of downtown DC, counted on October 3, 2026. The four rules that each plant’s “Find” reason refers to: (A) the estimate is the confirmed sightings, plus the unconfirmed ones (scaled down where the plant has lookalikes in its genus), plus the sightings marked as planted; (B) the tier by estimate: 1,500 or more is tier 1, 250–1,499 tier 2, 50–249 tier 3, under 50 tier 4; (C) tier 1, Everywhere, also needs a source saying the plant is common in lawns, sidewalks, yards or gardens, vacant lots or towns, or at least one DC street tree of it per km of sidewalk, otherwise it is tier 2; (D) if a reliable source says the plant is rare in this region, or that wild plants rarely bear the harvest, only planted sightings count. iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.

Effort: what this means

1 Grab & eat · 2 Quick kitchen prep (under about 30 minutes) · 3 Real work (hours, or cooking needed for safety) · 4 Project (days or equipment). Scored on the simplest worthwhile use; each plant’s page says why.

Sources

30 sources, each linked to the original.

  1. Rock Creek Park Superintendent’s Compendium National Park ServiceBacks up: picking rules
  2. 36 CFR 2.1 - Preservation of natural, cultural and archeological resources Legal Information Institute, Cornell Law School (text of federal regulation)Backs up: picking rules
  3. Sagittaria latifolia (Broad-leaved Arrowhead, Duck Potato, Wapato) NC State Extension Gardener Plant ToolboxBacks up: description, habitat, uses, safety, native or invasive status
  4. Arrowhead, Sagittaria spp. (Publication 3735-17; Neal, Riecke & Turnage) Mississippi State University Extension ServiceBacks up: description, safety
  5. Plant Fact Sheet: Duck Potato, Sagittaria latifolia USDA NRCS Plant Materials ProgramBacks up: description, season, safety
  6. Plant Guide: Broadleaf Arrowhead, Sagittaria latifolia USDA NRCS National Plant Data CenterBacks up: description, uses, season, picking rules, storage, keeping
  7. Wapato: All It’s Quacked Up To Be (Green Deane) Eat The WeedsBacks up: description, uses, season, safety, storage, keeping
  8. iNaturalist research-grade observations of Sagittaria latifolia within 25 km of downtown DC iNaturalistBacks up: findability
  9. Sagittaria latifolia Willdenow (Broad-leaved Arrowhead, Duck Potato, Wapato) (Digital Atlas of the Virginia Flora) Virginia Botanical Associates (Digital Atlas of the Virginia Flora)Backs up: habitat
  10. Annotated Checklist of the Vascular Plants of the Washington-Baltimore Area, Part II: Monocotyledons (Shetler & Orli, 2002) Smithsonian Institution, National Museum of Natural History, Department of BotanyBacks up: habitat
  11. Harvesting and storing home garden vegetables University of Minnesota ExtensionBacks up: keeping
  12. Packaging and Storing Dried Foods National Center for Home Food Preservation (University of Georgia)Backs up: keeping
  13. USDA PLANTS Database: Sagittaria latifolia (SALA2), native status USDA NRCSBacks up: native or invasive status
  14. Virginia Invasive Plant Species List (effective date: September 2024) Virginia Department of Conservation and Recreation, Division of Natural HeritageBacks up: native or invasive status
  15. Maryland Prohibited Invasive Plant Law and Regulations (Maryland Prohibited Invasive Plant List, updated January 2026; additions effective July 15, 2026; 'Next Plants To Be Assessed' 2026-2027) Maryland Department of Agriculture, Plant Protection & Weed ManagementBacks up: native or invasive status
  16. Non-Native Invasive Terrestrial Plant Species in the State of Maryland (updates approved through the April 18, 2024 MISC meeting) Maryland Invasive Species CouncilBacks up: native or invasive status
  17. Plant Invaders of Mid-Atlantic Natural Areas, Field Guide (Swearingen & Fulton, 2022; successor to the NPS/USFWS 5th ed., 2017) Mid-Atlantic Invasive Plant Council / Passiflora Press (hosted by Bugwood/Mid-Atlantic Invaders Tool)Backs up: native or invasive status
  18. Invasive Plants in the District DC Department of Energy & EnvironmentBacks up: native or invasive status
  19. Arrowhead (aquatic plant ID and treatment) Virginia Department of Wildlife ResourcesBacks up: safety
  20. Peltandra virginica (Green Arrow-arum, Tuckahoe) NC State Extension Gardener Plant ToolboxBacks up: safety
  21. Tuckahoe, Arrow Arum: Peltandra virginica, Starch Storer (Green Deane) Eat The WeedsBacks up: safety
  22. Arrow Arum (Chesapeake Bay field guide) Chesapeake Bay ProgramBacks up: safety
  23. Pontederia cordata (Pickerelweed) NC State Extension Gardener Plant ToolboxBacks up: safety
  24. Biology and Management of Sagittaria latifolia Willd. (Broad-leaf Arrow-head) for Wetland Restoration and Creation (Marburger, Restoration Ecology 1(4), 1993), abstract Crossref metadata record (Wiley, Restoration Ecology)Backs up: safety
  25. Edible Aquatic Plants in Farm Ponds (CNRE-127NP; Crosby, Nerrie & Gregg, 2021, reviewed 2026) Virginia Cooperative Extension (Virginia Tech and Virginia State University)Backs up: safety
  26. Arrow Arum (Peltandra virginica) Jefferson Patterson Park & Museum (Maryland Historical Trust, the State Museum of Archaeology), via the Internet ArchiveBacks up: safety
  27. Calla palustris (Wild Calla) NC State Extension Gardener Plant ToolboxBacks up: safety
  28. About Liver Flukes US Centers for Disease Control and PreventionBacks up: safety
  29. Pontederia cordata: In a PR Pickerel (Green Deane) Eat The WeedsBacks up: safety details
  30. iNaturalist research-grade observations of Sagittaria latifolia within 25 km of Washington, DC, by month (all observations) iNaturalistBacks up: season