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A Forager’s Year

No. 140

Black gum

Nyssa sylvatica

black tupelo, sour gum, pepperidge

Fruit ripe fruit (thin, sour flesh around a pit)

Drawing: Britton & Brown, Illustrated Flora (1913)

Find
Everywhere
Effort
Grab & eat
ID risk
Beginner
Origin
native
Uses
  • Eat raw / salad
  • Pesto & sauces
  • Baking & desserts
  • Jam & jelly
  • Syrup & cordial
  • Juice & drinks

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: At least one park allows it. 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.

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 tree of the tupelo family (NC State; also placed in the dogwood family, Virginia Tech), 40 to 70 feet tall, whose slender branches grow out at right angles to the trunk (NC State). Its glossy, dark green leaves turn yellow, orange, red or purple in fall, and old bark is deeply furrowed into square or rectangular blocks (NC State) that resemble alligator hide (Virginia Tech). Only female trees bear fruit (NC State). The fruit is a round to oval drupe 3/8 to 1/2 inch long that ripens from green to bluish-black, with thin, bitter-smelling flesh around a small, ribbed pit (NC State); it hangs 1 to 3 together on long, slender stems (Maine Forest Service). NC State calls the fruit edible but sour, and Alabama Extension calls it richly flavored but small, with a large seed and relatively little flesh. Taste varies from tree to tree, from palatable and sweet to strongly sour or bitter, and cooking mellows it (Tyrant Farms); Eat The Weeds calls the raw pulp extremely sour and extremely bitter. Picking is hard because the trees are tall and birds almost always get to the fruit first (Alabama Extension).

Safety

No toxicity is reported for the fruit in the sources checked: NC State lists no poisonous part of black gum and calls the fruit edible but sour. Alabama Extension advises making sure a wild tree is correctly identified, washing the fruit well and using only intact, fully ripe fruit. Harmless lookalikes: swamp tupelo, whose fruit looks the same and is also eaten (Tyrant Farms), grows in Coastal Plain swamps and has narrower leaves (NC State; Virginia plant atlas). Wild black cherry’s single fruits look similar (Tyrant Farms), but black cherry’s hang in drooping clusters and ripen in late summer (NC State), while black gum’s hang 1 to 3 together on long stems and ripen in fall (Maine Forest Service); black cherry is eaten with the pits removed, and NC State lists its fruit, leaves and seeds as poisonous parts. American persimmon and sourwood are confused with the tree rather than the fruit (NC State; Virginia Tech): persimmon’s fruit is large, orange and fleshy (University of Illinois Extension), and sourwood bears dry capsules (NC State). Water tupelo, also named as a lookalike (NC State; Virginia Tech), is not recorded near DC.

Lookalikes

  • American persimmon Diospyros virginiana harmless (may be edible)

    NC State lists persimmon as often confused with black gum, and Virginia Tech says black gum looks like persimmon. Persimmon’s fruit is large, orange and fleshy, while black gum’s is small and dark blue to black when ripe (University of Illinois Extension); persimmon fruit is 1 to 1 1/2 inches long (NC State). Black gum leaves are thinner, end in an abrupt, pinched point and turn bright red to deep scarlet in fall, and black gum leaf scars show three dots; persimmon leaves taper gradually and its leaf scars are crescent-shaped (University of Illinois Extension). Ripe persimmons are themselves eaten.

  • Sourwood (sorrel tree) Oxydendrum arboreum harmless (may be edible)

    Virginia Tech lists sourwood as looking like black gum. Sourwood bears dry, brownish capsules 1/3 to 1/2 inch long that ripen to silver-gray, not fleshy fruit, and its glossy leaves are finely toothed and taste sour (NC State). NC State lists no poisonous part for sourwood.

  • Swamp tupelo Nyssa biflora harmless (may be edible)

    Virginia Tech lists swamp tupelo as looking like black gum, and Tyrant Farms says its fruit looks identical, is also edible and ripens at the same time. Swamp tupelo grows in swamps, often with cypress, and has narrower leaves and deeply ridged seeds (NC State; Lady Bird Johnson Wildflower Center). In Virginia it is common in the southern and central Coastal Plain and rarely reaches the extreme eastern Piedmont (Virginia plant atlas).

  • Water tupelo Nyssa aquatica harmless (may be edible)

    Not recorded near DC. NC State lists water tupelo as often confused with black gum, and Virginia Tech says black gum looks like it. It grows in river swamps, often with bald cypress, in Virginia’s southern and central Coastal Plain (Virginia plant atlas), and its trunk is conspicuously enlarged at the base (Eat The Weeds). Eat The Weeds calls its fruit edible.

  • Black cherry (wild black cherry) Prunus serotina harmless (may be edible)

    Tyrant Farms warns that wild black cherry could be confused with black gum because the single fruits look alike, though they ripen months apart. Black cherry has 3/8-inch purple-black cherries in drooping clusters that ripen in late summer (NC State), while black gum’s fruit hangs 1 to 3 together on long, slender stems (Maine Forest Service) and ripens in fall. Black cherry is eaten with the pits removed; NC State rates its poison severity as medium and lists its fruit, leaves and seeds as poisonous parts.

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
Beginner
Why
No toxic lookalike is named. Swamp tupelo and wild black cherry have similar dark fruit and are eaten too: swamp tupelo grows in Coastal Plain swamps, and black cherry’s fruit hangs in drooping clusters and ripens in late summer, while black gum’s hangs 1 to 3 together on long stems and ripens in fall (Tyrant Farms; NC State; Maine Forest Service). Persimmon and sourwood are confused with the tree, not the fruit: persimmon’s fruit is large and orange, sourwood’s a dry capsule (University of Illinois Extension; NC State).
Soil risk
low
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 Sep
Peak
late Sep–mid Oct
Ends
early Nov

The USDA Forest Service says black gum fruit ripens in September and October and drops from September through November. NC State gives September to October for the bluish-black fruit, Virginia Tech says late summer and fall, and Penn State Extension says the fruit develops in the fall. The fruit ripens from green to bluish-black (NC State). Birds and other wildlife eat it from August through October (NC State), and birds almost always get to it before it falls (Alabama Extension). Around DC, few iNaturalist sightings are marked as fruiting, and the latest fall in mid-October, so the end of the season is an estimate.

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: peak, end

Start

sourced

Peak

estimated: No source names a peak. Late September to mid October is the middle of the September–October ripening window, when the DC fruiting records cluster, before birds have stripped most trees.

End

estimated: No regional source dates the last usable fruit. Fruit drop runs into November (USDA Forest Service), but birds take most fruit early (Alabama Extension) and DC fruiting records end in mid October, so the end is placed in early November rather than late November.

Evidence

start: USDA Forest Service (Silvics): 'The fruit of black tupelo ripens in September and October and drops from September through November.' Woody Plant Seed Manual, table 2 (N. sylvatica): fruit ripening Sept–Oct, ripe color blue-black. NC State: 'bluish-black drupes from September to October'. Virginia Tech (Virginia): fruit 'ripen in late summer and fall'. Eat The Weeds: 'Fruits usually in September or October'. | peak: USDA Forest Service: ripens September and October. NC State: wildlife eat the fruit 'from August through October'. Alabama Extension: 'birds almost always get to the fruit before they fall'. iNaturalist, 25 km of DC, research grade, fruiting annotation, by week: weeks 35 (2), 38 (3), 39 (3), 40 (1), 41 (3); by month, September 7, October 4. | end: USDA Forest Service (Silvics; Woody Plant Seed Manual): fruit drops September through November. iNaturalist, 25 km of DC, research grade, fruiting annotation: last record in week 41 (mid October); no fruiting record in November or later.

Where to look

Oak-hickory upland woods, stream valleys and swampy low woods, and often planted as a street tree; only female trees bear fruit. Logged most in Rock Creek Park, Huntley Meadows Park, Glencarlyn Park and Barcroft Park, where picking is not allowed, and on the University of Maryland campus, whose picking rules were not checked. Virginia state parks allow picking edible fruit, and a few black gums are logged at Mason Neck and Leesylvania; the C&O Canal allows edible fruits generally but sets no limit for black gum, so it is ambiguous there (ask the park). Otherwise pick from private trees with the owner’s permission.

Habitats
street & yard trees (planted), floodplain & stream-valley forest, upland oak-hickory woods, 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.

Ask first: rules unclear or not checked

  • University of Maryland, College Park campus

    26 sightings · Legal to pick: unknown · see them on iNaturalist

    Picking rules not checked.

No picking here (4 places)
  • Rock Creek Park

    78 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.

  • Huntley Meadows Park

    53 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.

  • Glencarlyn Park

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

    Look but don’t pick: Arlington County park rules say flora shall not be removed or disturbed.

  • Barcroft Park

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

    Look but don’t pick: Arlington County park rules say flora shall not be removed or disturbed.

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

  • eat raw as a nibble: the thin, sharply acid pulp is pleasant to roll in the mouth (NC State); chew it like gum, without the stone (Eat The Weeds)
  • jelly and preserves (NC State; Alabama Extension; Eat The Weeds)
  • flavored drinks, ice cream or other dishes (Alabama Extension)
  • cooked juice: mash the fruit with a couple of tablespoons of water, cook 15 to 20 minutes, strain out the skins and pits, and sweeten the juice for sauces or a honey butter (Tyrant Farms)
  • fermented cordial, made the same way as a wild black cherry cordial (Tyrant Farms)
  • gather fallen fruit that is still in good shape from under fruit-bearing trees; only female trees bear fruit (Tyrant Farms; NC State)

Keeping

Refrigerate unwashed and use, cook or freeze it within 1 to 3 days; there is no tested canning recipe for black gum.

Use within
within a few days
Keeps fresh
General guidance for soft berries: remove moldy or damaged fruit, refrigerate unwashed and use within 1 to 3 days (Utah State University Extension). No storage data specific to black gum was found.
Canning
no tested recipe: refrigerate or freeze, don’t can
Keeping basis
general guidance for its type

Ways to keep it

  • Ferment as researched: ferment; canning: n/a (not shelf-canned)

    Tyrant Farms makes a fermented black gum cordial with its wild black cherry cordial recipe.

  • Freeze as researched: freeze; canning: n/a (not shelf-canned)

    Tray-freeze whole fruit in a single layer and package it as soon as it is frozen, or dry-pack it without sugar (general guidance for berries, NCHFP).

  • Jam/jelly as researched: jam/jelly; canning: no tested recipe — refrigerate or freeze

    Used for jelly and preserves (NC State; Alabama Extension), but no NCHFP or other extension-tested canning recipe names black gum, so keep the jelly refrigerated or frozen rather than canning it.

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
eastern North America, from southern Maine and southern Ontario south to Florida and eastern Texas; also Mexico
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
Everywhere Estimate 2,292 = 1,127 research-grade iNaturalist sightings within 25 km + 1,029 needs-ID sightings counted at 100% (1,127 of the 1,128 research-grade Nyssa sightings here are black gum) + 137 'cultivated' (planted) sightings (rule A); that is tier 1 by count (rule B). Rule C (everyday place) is met: DC’s street-tree inventory lists 3,279 living black gums, more than one per km of DC sidewalk (2,406). Final tier 1.
Effort
Grab & eat Pick ripe fruit from low branches, or gather fallen fruit in good shape, and roll the thin, sharply acid pulp off the pit as a nibble; mashing, cooking and straining the fruit for juice, jelly or a sauce is a 2.
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

34 sources, each linked to the original.

  1. C&O Canal NHP Superintendent’s Compendium, effective September 11, 2026 National Park Service, Chesapeake and Ohio Canal NHPBacks up: picking rules
  2. Prince William Forest Park Superintendent’s Compendium National Park Service, Prince William Forest ParkBacks up: picking rules
  3. 4VAC5-30-50. Flowers, plants, minerals, etc. Virginia Law Library (law.lis.virginia.gov)Backs up: picking rules
  4. Rock Creek Park Superintendent’s Compendium (2026) National Park ServiceBacks up: picking rules
  5. Black tupelo Maine Forest Service (Maine Department of Agriculture, Conservation and Forestry)Backs up: description, safety, safety details
  6. blackgum (Nyssa sylvatica) fact sheet Virginia Tech DendrologyBacks up: description, season, safety, safety details
  7. Nyssa sylvatica (Black Gum, Black Tupelo) NC State Extension Gardener Plant ToolboxBacks up: description, season, uses, habitat, safety, picking rules, native or invasive status, keeping
  8. Black tupelo fruit: how to ID & use (with recipe) Tyrant FarmsBacks up: description, uses, safety, keeping
  9. Tupelos: Black, Swamp, Bear, Water, Ogeechee (Green Deane) Eat The WeedsBacks up: description, uses, season, safety
  10. Native Fruits: Tupelo Alabama Cooperative Extension SystemBacks up: description, uses, season, safety, keeping
  11. iNaturalist research-grade observations of Nyssa sylvatica within 25 km of downtown DC iNaturalistBacks up: findability
  12. Annotated Checklist of the Vascular Plants of the Washington-Baltimore Area, Part I (Shetler & Orli, 2000) Smithsonian Institution, National Museum of Natural History, Department of BotanyBacks up: habitat
  13. Nyssa sylvatica Marshall (Black Gum, Sour Gum) Digital Atlas of the Virginia Flora (Virginia Botanical Associates)Backs up: habitat, findability
  14. DC street-tree inventory (DDOT Urban Forestry, UFA Street Trees layer): living trees by species, queried 2026-10-05 (2,822 Nyssa sylvatica + 457 'Wildfire' = 3,279 living black gums) District of Columbia (DDOT Urban Forestry Division, via DC GIS)Backs up: habitat, findability
  15. Nyssa sylvatica (Black tupelo, blackgum) Lady Bird Johnson Wildflower Center (University of Texas at Austin)Backs up: habitat, safety
  16. USDA PLANTS Database: Nyssa sylvatica (NYSY), native status USDA NRCSBacks up: native or invasive status
  17. Virginia Invasive Plant Species List (effective date: September 2024) Virginia Department of Conservation and Recreation, Division of Natural HeritageBacks up: native or invasive status
  18. 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
  19. 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
  20. 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
  21. Invasive Plants in the District DC Department of Energy & EnvironmentBacks up: native or invasive status
  22. Diospyros virginiana (American persimmon) NC State Extension Gardener Plant ToolboxBacks up: safety details
  23. Nyssa aquatica L. (Water Tupelo) Digital Atlas of the Virginia Flora (Virginia Botanical Associates)Backs up: safety details
  24. Tree Identification: Distinguishing Persimmon and Black Gum Leaves and Twigs University of Illinois ExtensionBacks up: safety, safety details
  25. Oxydendrum arboreum (sourwood) NC State Extension Gardener Plant ToolboxBacks up: safety, safety details
  26. Prunus serotina (black cherry) NC State Extension Gardener Plant ToolboxBacks up: safety, safety details
  27. Nyssa biflora Walt. (Swamp Tupelo, Swamp Black Gum) Digital Atlas of the Virginia Flora (Virginia Botanical Associates)Backs up: safety, safety details
  28. Nyssa L., tupelo (Woody Plant Seed Manual, Agriculture Handbook 727) USDA Forest ServiceBacks up: season
  29. Rain Garden Plants: Black Gum Penn State ExtensionBacks up: season
  30. Black tupelo research-grade observations within 25 km of DC, by week of year (fruiting annotation) iNaturalistBacks up: season
  31. Black tupelo research-grade observations within 25 km of DC, by month (fruiting annotation) iNaturalistBacks up: season
  32. Black tupelo (Silvics of North America) USDA Forest ServiceBacks up: season, habitat, native or invasive status
  33. How to Preserve Berries Utah State University ExtensionBacks up: storage, keeping
  34. Dry or Tray Packing for Fruits National Center for Home Food Preservation (University of Georgia)Backs up: storage, keeping