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A Forager’s Year

No. 175

Wild potato vine

Ipomoea pandurata

man-of-the-earth, wild sweet potato

Roots, bulbs & tubers young roots (boiled in changes of water; never raw)

Drawing: Britton & Brown, Illustrated Flora (1913)

Find
Common in the right habitat
Effort
Real work
ID risk
Careful
Origin
native
Safety marks
  • Toxic lookalike
  • Toxic parts
  • Cook first
Uses
  • Cooked vegetable / soup

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

A native perennial vine of the morning glory family that trails along the ground or climbs over other plants, reaching up to 30 feet (NC State). Its leaves are heart-shaped, sometimes fiddle-shaped, and 3 to 6 inches long with a pointed tip, and its stems are often purplish (NC State; Illinois Wildflowers). The large, funnel-shaped flowers are white with a reddish-purple eye deep in the throat; they open in the morning and the plant blooms from May to September (NC State; Illinois Wildflowers). Its seeds are hairy, while other morning glories and bindweeds usually have smooth seeds (Illinois Wildflowers). Below ground it forms a huge, starchy root that grows straight down and can reach 4 feet long and 25 to 30 pounds (NC State). NC State says the roots can be eaten cooked but are a purgative raw, and Illinois Wildflowers calls the cooked root edible, if barely. Eat The Weeds says younger and smaller roots are better, because roots get more acrid as they age. A forager writing in Acres U.S.A. says the baked strips smell like sweet potato but do not taste like it, and that their texture reminds him of meat.

Safety

Never eat the root raw: NC State says the roots can be eaten cooked but are a purgative raw, and Eat The Weeds says to cube the root and boil it in at least two changes of water. A review of the genus in Revista Brasileira de Farmacognosia, a peer-reviewed pharmacy journal, says resin glycosides in the roots and leaves of the morning glory family are responsible for the purgative properties of some species. Do not eat the seeds: NC State rates wild potato vine a low-severity poison, with vomiting as a symptom, and says large amounts of seeds may cause hallucinations (they contain lysergic-acid-type alkaloids); Poison Control says morning glory seeds can be poisonous, especially in large quantities, with symptoms from diarrhea to hallucinations. Plants For A Future, a plant database, notes a report that the root could be poisonous; no safety source confirms that for the cooked root. Toxic lookalike: other morning glories, including the common morning glory and the ivy-leaved morning glory, are among the plants most likely to be confused with it (University of Michigan). The common morning glory is an annual vine (NC State) whose flowers are purple, deep rose or white with white centers (Plant Invaders of Mid-Atlantic Natural Areas), and NC State rates it a low-severity poison with the same seed warning; wild potato vine is a perennial with white flowers with a reddish-purple eye and a huge root (NC State), and its seeds are hairy (Illinois Wildflowers). Other lookalikes with possible hazards: the small white morning glory has small white flowers (Eat The Weeds), and NC State lists morning glory seeds as poisonous (low severity). Wild yam has heart-shaped leaves with arching veins that meet at the tip, whorled lower leaves and much smaller flowers (University of Michigan); it does not produce edible tubers (NC State), and Memorial Sloan Kettering Cancer Center notes it caused chronic kidney injury in animal studies. Harmless lookalikes: hedge and large bindweeds have all-white flowers, often without a red throat, with bracts enclosing the base of the flower (University of Michigan; Eat The Weeds); Eat The Weeds says bindweed roots are edible cooked but can be purgative. Field bindweed has small arrowhead-shaped leaves and flowers under an inch across (NC State); Ohio State University finds no reports that it is poisonous to people. Chinese yam, an invasive vine with large yam-like tubers that was brought to the U.S. partly as a food plant, bears small potato-like bulbils in its leaf axils and rarely flowers, while wild potato vine has no bulbils and large white flowers with purple centers (Plant Invaders of Mid-Atlantic Natural Areas). The root is dug after the vine has died back, so find and mark the plant in summer (Acres U.S.A.).

Lookalikes

  • Common morning glory (and other annual morning glories, such as ivy-leaved morning glory) Ipomoea purpurea (also Ipomoea hederacea) toxic

    The University of Michigan lists the common and ivy-leaved morning glories among the plants most likely to be confused with wild potato vine. The common morning glory is an annual vine (NC State) whose flowers are purple, deep rose or white with white centers (Plant Invaders of Mid-Atlantic Natural Areas); NC State rates it a low-severity poison: vomiting, and large amounts of seeds may cause hallucinations; Poison Control says morning glory seeds can be poisonous. Ivy-leaved morning glory has hairy stems, hairy pointed sepals, leaves that can be 3-lobed and a smaller blue, pink or purple flower with a white tube (University of Michigan). Wild potato vine is a perennial with white flowers with a reddish-purple eye and a huge starchy root (NC State), and its seeds are hairy, while other morning glories usually have smooth seeds (Illinois Wildflowers).

  • Small white morning glory (whitestar) Ipomoea lacunosa toxic

    Eat The Weeds says it is similar to wild potato vine except for its small white flowers, and that its cooked root was eaten by American Indians. NC State lists the seeds of morning glories (genus Ipomoea) as poisonous (low severity).

  • Wild yam Dioscorea villosa toxic

    Listed by the University of Michigan as likely to be confused with wild potato vine for its heart-shaped leaves; wild yam’s lower leaves are whorled and all its leaves have arching veins that meet at the tip, and its flowers are much smaller, while wild potato vine’s leaves are all alternate (University of Michigan). NC State says wild yam has slender rhizomes and does not produce edible tubers, and Memorial Sloan Kettering Cancer Center notes that wild yam has caused chronic kidney injury in animal studies.

  • Hedge bindweed and large bindweed Calystegia sepium, Calystegia silvatica harmless (may be edible)

    Eat The Weeds names hedge bindweed with wild potato vine among the white-flowered morning glory relatives, and the University of Michigan lists large bindweed as likely to be confused with it. Bindweed flowers are white, often without a red throat (Eat The Weeds), with bracts enclosing the base of the flower, and the leaves have a wider, sometimes square notch at the base (University of Michigan); NC State describes hedge bindweed’s leaves as triangular. Eat The Weeds says bindweed stalks, young shoots and roots are edible cooked but can be purgative, so regular eating is not recommended; NC State lists no poison information for hedge bindweed.

  • Field bindweed Convolvulus arvensis harmless (may be edible)

    Listed by the University of Michigan as likely to be confused with wild potato vine. Field bindweed has small arrowhead-shaped leaves 1 to 2 inches long and funnel-shaped flowers about 3/4 inch across (NC State), pink or white with pink stripes (University of Michigan). Ohio State University’s weed guide finds no reports that it is poisonous to people but says its seeds are suspected of containing toxic substances; no source checked calls it edible.

  • Chinese yam (cinnamon vine) Dioscorea polystachya harmless (may be edible)

    Plant Invaders of Mid-Atlantic Natural Areas names wild potato vine as a look-alike of this invasive vine, which also has large, elongated, yam-like underground tubers and was brought to the U.S. partly as a food plant. Chinese yam bears small, round, potato-like bulbils in the leaf axils and rarely flowers in the U.S.; wild potato vine has no bulbils and has large, showy white flowers with purple centers (Plant Invaders of Mid-Atlantic Natural Areas).

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
Other morning glories, including the common morning glory, whose seeds are poisonous (NC State; Poison Control), are among the plants most likely to be confused with it (University of Michigan). Wild potato vine has white flowers with a reddish-purple eye, hairy seeds and a huge starchy root (NC State; Illinois Wildflowers), while the common morning glory is an annual (NC State) whose purple, deep rose or white flowers have white centers (Plant Invaders of Mid-Atlantic Natural Areas). The root is dug after the vine dies back, so mark the plant in summer (Acres U.S.A.). Wild yam (kidney injury in animal studies, Memorial Sloan Kettering Cancer Center) and the small white morning glory (poisonous seeds, NC State) are also toxic lookalikes; bindweeds and Chinese yam are harmless lookalikes.
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
early Oct
Peak
early Nov–late Feb
Ends
mid Apr

The Lady Bird Johnson Wildflower Center says Indigenous people reputedly harvested the large taproot from fall to spring. A forager writing in Acres U.S.A. says the plant stores more of its energy in the root during the fall and winter months, and advises finding and marking the vine in summer and digging the root in winter. The vine blooms from May to September and its seed capsules show from July to October (NC State). In the DC area, iNaturalist sightings drop off sharply after September, so the plant is hard to find once the vine dies back. No source gives digging 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 of the dig for the DC area; early October follows the end of flowering (September, NC State) and Lady Bird Johnson Wildflower Center’s fall start, when the season’s growth is finished.

Peak

estimated: No source names a best month for the DC area; November through February covers the late fall and winter digging that Acres U.S.A. (an Alabama forager) recommends, after the vine is done and before spring growth.

End

estimated: No DC-area source gives an end; mid April keeps Lady Bird Johnson Wildflower Center’s fall-to-spring harvest and ends before the first spring sightings of the vine in late April.

Evidence

start: Lady Bird Johnson Wildflower Center: 'Indigenous people reputedly harvested the large taproot from fall to spring for food.' NC State: 'Blooms from May to September' and the capsule 'Displays from July to October.' iNaturalist (DC, 25 km, research grade, by week): 15, 5 and 2 sightings in weeks 36-38, then 1 each in weeks 40 and 43. | peak: Acres U.S.A.: 'more of the plant’s energy is stored in the root during the fall and winter months, so locating and marking the plant in summer and digging the root up in the winter gives the forager more energy'. | end: Lady Bird Johnson Wildflower Center: harvested 'from fall to spring'. iNaturalist (DC, 25 km, research grade, by week): the first sightings of the year are 3 in week 17 (late April).

Where to look

Thickets, fence rows, abandoned fields, dry woods and rocky river shores, logged most along the C&O Canal, on the Sligo Creek powerline meadow (Pepco land), at Great Falls Park (VA), in Sligo Creek Stream Valley Park and in Rock Creek Park, where digging is not allowed; dig only on private land with the owner’s permission, after marking the vine in summer.

Habitats
old fields & meadows, woods edges, trailsides & thickets, upland oak-hickory woods
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)
  • C&O Canal NHP (towpath, Georgetown to Great Falls MD and beyond)

    71 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, 1 is at Carderock.

  • Sligo Powerline Meadow (Pepco land)

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

    Pepco transmission-line land. Private property: pick only with the owner’s permission.

  • Great Falls Park (VA)

    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.

  • Sligo Creek Stream Valley Park

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

    Look but don’t pick: Montgomery/Prince George’s parks (M-NCPPC) ban harvesting vegetation without a permit.

  • Rock Creek Park

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

    Look but don’t pick: Rock Creek Park’s compendium bans gathering any fruit, nut, berry, seed or greenery.

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

  • root cut in cubes and boiled in at least two changes of water, never eaten raw (Eat The Weeds)
  • boiled cubes roasted afterward (Eat The Weeds); Acres U.S.A. bakes the boiled root at 400°F for about 40 minutes like a sweet potato, then peels it, cuts it into strips and seasons them with butter, salt and pepper
  • harvest: find and mark the vine in summer, follow it down to the base and dig the root in winter (Acres U.S.A.); the root usually lies straight down from where the vine enters the ground (Eat The Weeds)
  • harvest the younger, smaller roots and leave big old ones, which are more acrid (Eat The Weeds)

Keeping

Keep cold and moist for a few weeks, or slice and dry them for longer storage.

Use within
weeks
Keeps fresh
Weeks refrigerated in a perforated bag, or longer in cold, moist storage (general guidance for root crops). Univ. of Minnesota: perforated plastic bags in the refrigerator give cold and moist conditions for a moderate time; root cellars give them too.
Keeping basis
general guidance for its type

Ways to keep it

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

    Acres U.S.A.: a forager cut the root into pieces about 1/4 inch thick, dried them in full sun and kept them on a pantry shelf for months, then rehydrated them in water before cooking. NCHFP: store dried foods in cool, dry, dark areas, for 4 months to 1 year (general guidance for dried foods).

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

    Univ. of Minnesota: root crops keep in cold and moist conditions (32 to 40°F, 95 percent relative humidity), which root cellars provide (general guidance for root crops).

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
southeastern Canada to the central and eastern United States (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 270 = 261 research-grade iNaturalist sightings within 25 km + 28 needs-ID sightings counted at 25% (261 of the 1,033 research-grade Ipomoea sightings here are wild potato vine) + 2 'cultivated' (planted) sightings (rule A); that is tier 2 by count (rule B). Rule D does not apply: no source checked calls it rare in DC or the region (the University of Michigan’s note that it is threatened in Michigan and endangered in New York is about other states), and the Digital Atlas of the Virginia Flora calls it "Common throughout." Final tier 2.
Effort
Real work Find and mark the vine in summer, then dig the deep root in winter, which can take some time for roots 12 to 24 inches or longer (Acres U.S.A.) that can reach 4 feet (NC State); cut it in cubes and boil it in at least two changes of water before eating or roasting (Eat The Weeds).
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. Wild Sweet Potato (Ipomoea pandurata) (John Hilty) Illinois WildflowersBacks up: description, habitat, safety, findability
  4. Ipomoea: Water, Land, See in Gardens (Green Deane) Eat The WeedsBacks up: description, uses, safety
  5. iNaturalist research-grade observations of Ipomoea pandurata within 25 km of downtown DC iNaturalistBacks up: findability
  6. Annotated Checklist of the Vascular Plants of the Washington-Baltimore Area, Part I (Shetler & Orli, 2000) Smithsonian Institution, National Museum of Natural HistoryBacks up: habitat
  7. Ipomoea pandurata (Wild Potato-vine, Manroot, Man-of-the-earth) (Digital Atlas of the Virginia Flora) Virginia Botanical Associates (Digital Atlas of the Virginia Flora)Backs up: habitat, picking rules, findability
  8. Harvesting and storing home garden vegetables University of Minnesota ExtensionBacks up: keeping
  9. Packaging and Storing Dried Foods National Center for Home Food Preservation (University of Georgia)Backs up: keeping
  10. USDA PLANTS Database: Ipomoea pandurata (IPPA), native status USDA NRCSBacks up: native or invasive status
  11. Virginia Invasive Plant Species List (effective date: September 2024) Virginia Department of Conservation and Recreation, Division of Natural HeritageBacks up: native or invasive status
  12. 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
  13. 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
  14. Invasive Plants in the District DC Department of Energy & EnvironmentBacks up: native or invasive status
  15. Are morning glories poisonous? National Capital Poison Center (Poison Control)Backs up: safety, effort & ID risk, safety details
  16. Ipomoea purpurea (Common Morning Glory) NC State Extension Gardener Plant ToolboxBacks up: safety, effort & ID risk, safety details
  17. Calystegia sepium (Hedge Bindweed) NC State Extension Gardener Plant ToolboxBacks up: safety, effort & ID risk, safety details
  18. Convolvulus arvensis (Field Bindweed) NC State Extension Gardener Plant ToolboxBacks up: safety, effort & ID risk, safety details
  19. Dioscorea villosa (Wild Yam) NC State Extension Gardener Plant ToolboxBacks up: safety, effort & ID risk, safety details
  20. Wild Yam (About Herbs, Botanicals & Other Products) Memorial Sloan Kettering Cancer CenterBacks up: safety, effort & ID risk, safety details
  21. Ipomoea (Cypress Vine, Morning Glory), genus page NC State Extension Gardener Plant ToolboxBacks up: safety, effort & ID risk, safety details
  22. Field Bindweed (Convolvulus arvensis), Ohio Perennial and Biennial Weed Guide The Ohio State University, College of Food, Agricultural, and Environmental SciencesBacks up: safety, effort & ID risk, safety details
  23. Ipomoea pandurata, CLIMBERS species account (R. J. Burnham) University of MichiganBacks up: safety, findability, effort & ID risk, safety details
  24. Plant Invaders of Mid-Atlantic Natural Areas, Field Guide (Swearingen & Fulton, 2022), Chinese yam, pp. 158-159 Mid-Atlantic Invasive Plant Council / Passiflora Press (hosted by Bugwood/Mid-Atlantic Invaders Tool)Backs up: safety, native or invasive status, effort & ID risk, safety details
  25. Review of the genus Ipomoea: traditional uses, chemistry and biological activities (Meira et al., 2012), Revista Brasileira de Farmacognosia 22(3) Revista Brasileira de Farmacognosia (SciELO Brasil)Backs up: safety, safety details
  26. Ipomoea pandurata (Plants For A Future database) Plants For A FutureBacks up: safety, safety details
  27. Ipomoea pandurata (Man of the Earth, Wild Potato) Lady Bird Johnson Wildflower CenterBacks up: season
  28. iNaturalist research-grade observations of Ipomoea pandurata within 25 km of Washington, DC, by week (all observations) iNaturalistBacks up: season
  29. Ipomoea pandurata (Wild Potato Vine, Man-of-the-Earth) NC State Extension Gardener Plant ToolboxBacks up: season, description, habitat, safety, native or invasive status
  30. Harvesting, Preparing Wild Potato (Dewayne Allday, June 2015) Acres U.S.A. (EcoFarming Daily)Backs up: season, description, uses, safety, storage, keeping