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A Forager’s Year

No. 42

Red mulberry

Morus rubra

Fruit ripe fruit

Drawing: Britton & Brown, Illustrated Flora (1913)

Find
Elusive
Effort
Grab & eat
ID risk
Beginner
Origin
native
Safety marks
  • Toxic parts
Uses
  • Eat raw / salad
  • Baking & desserts
  • Jam & jelly
  • Syrup & cordial
  • Juice & drinks
  • Wine & spirits
  • Dried fruit & leather

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

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. 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 understory tree with large leaves that are rough on top and softly hairy underneath. Leaves may be unlobed or have one or two lobes, and end in a pointed, elongated tip. The fruit looks like an elongated blackberry, about an inch long, ripening from red to deep purple-black. It is sweet and juicy.

Safety

Eat only fully ripe fruit. Unripe berries and the milky sap found in every part of the tree are mildly toxic and can cause stomach upset and hallucinations (NC State; Lady Bird Johnson Wildflower Center). The sap can also irritate skin. Wash the fruit, because trees over sidewalks and roads collect grime. Red and white mulberry hybridize freely, so many trees are hard to assign to one species, but the fruit of all of them is edible when ripe.

Safety flags

  • Handling hazard (minor)

    irritant sap/pulp: NC State lists contact dermatitis from the milky sap of red mulberry; avoid smearing broken twigs or leaf stalks on skin.

  • Toxic parts

    Unripe fruit and the milky sap throughout the tree are mildly toxic (stomach upset, hallucinations) per NC State.

Safety marks and flags: what this means

Deadly lookalike / Toxic lookalike: a cited source names a lookalike of that danger. 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 dangerous lookalike; red and white mulberries hybridize but all ripe mulberry fruit is edible. Avoid unripe berries, which are easy to tell by color and firmness.
Handling hazards
Irritant sap/pulp (minor)
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.

Handling hazards: what this means

Stings, thorns, irritating or phototoxic sap, staining hulls and spiny husks, with a severity: minor = brief discomfort; moderate = rash or blisters lasting days; serious = burns, scarring or medical care possible.

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
late May
Peak
early Jun–mid Jun
Ends
early Jul

The Natural History Society of Maryland says to start watching in the last week of May, with the season mostly in June, and NC State lists fruit in May and June. Red mulberry is much less common around DC than white mulberry and its hybrids, so there are few local records; Maryland and Virginia iNaturalist photos show ripe red mulberries from late May to mid-June, with a few into early July. Ripe red mulberries are plump, fully dark purple to nearly black, and come off the tree easily; red or green ones are not ripe (Natural History Society of Maryland).

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 first ripe fruit near DC; late May matches the earliest ripe-fruit photos in Maryland and Virginia.

Peak

estimated: No source names a peak week; early to mid June matches the June season and the dates of ripe-fruit photos.

End

estimated: Maryland sources describe a June season; the early-July end covers the last regional records and the July tail in USDA and Missouri sources.

Evidence

start: NC State: 'Fruit displays from May to June' (North Carolina). Natural History Society of Maryland: small green berries appear in the last week of May and the season 'tends to be in June'. iNaturalist MD/VA/DC fruiting photos of red mulberry from May 21, 26 and 27. | peak: Natural History Society of Maryland: the fruit-bearing season 'tends to be in June'. iNaturalist MD/VA/DC research-grade fruiting photos of Morus rubra (17 records) show fully dark fruit on May 26, Jun 1, Jun 7 and Jun 11. | end: USDA Forest Service Silvics (range-wide): fruit 'reaches full development from June to August'. MDC Wild Edibles gives May-July collection (Missouri). iNaturalist MD/VA/DC Morus rubra fruiting records run to weeks 25-27 (late Jun-early Jul: 1, 2), with a ripe-looking fruit on Jun 25.

Where to look

Scattered in rich bottomland woods, with a few trees logged at Piscataway Park (NACE does not list mulberries, so no picking) and along the C&O towpath (ambiguous: ask the park); Virginia state parks allow picking but have no logged trees, so this is mostly a private-land find.

Habitats
woods edges, trailsides & thickets, floodplain & stream-valley forest
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

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

    2 sightings · Legal to pick: ambiguous · see them on iNaturalist

    Ambiguous: the C&O compendium allows edible fruits, nuts and berries generally but sets no limit for this one; ask the park first. Of these, 2 are at Carderock.

No picking here (2 places)
  • Piscataway Park

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

    Look but don’t pick: a NACE gathering site, but this item is not on the compendium’s list.

  • Norwood Local Park

    2 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.

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 (rugosa rose) have no places. No most-logged places are named for at-risk plants (ramps, chinquapin, American chestnut); chinquapin’s page names Mason Neck State Park, where picking is legal, and asks you to leave most nuts. 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 fresh
  • jam, jelly, syrup, juice and wine
  • pies, cobblers, muffins, breads and cakes
  • freeze or dehydrate (very short shelf life fresh)
  • harvest by spreading a sheet or tarp and shaking the branches

Keeping

Process the same day you shake them down (next day at the latest) by freezing, drying or making jelly, because they barely keep.

Use within
pick & use same day
Keeps fresh
Very short shelf life (NC State). Best eaten the day you pick them or the next day.
Canning
lab-tested: jelly, whole berries (NCHFP)
Keeping basis
specific to this plant

Ways to keep it

  • Can as researched: can (water bath); canning: lab-tested: whole berries (NCHFP)

    Whole mulberries are on NCHFP’s tested 'Berries - Whole' list for boiling-water canning (raw pack).

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

    Dehydrating is a recommended way to store them (Natural History Society of Maryland).

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

    Tray-freeze in a single layer, then pack into containers as soon as frozen (NCHFP tray pack). Best quality for about 8-12 months at 0°F.

  • Jam/jelly as researched: jam/jelly; canning: lab-tested: jelly (NCHFP)

    NCHFP has a tested mulberry jelly using powdered pectin (3/4 ripe, 1/4 red berries, or add lemon juice if all are fully ripe), processed in a boiling-water canner.

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

Native, but hybridizes freely with invasive white mulberry (Morus alba); hybrids and white mulberry are common around DC, so 'red mulberry' trees may not be pure M. rubra.

Origin
native
Native range
eastern North America
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
Elusive Estimate 48 = 32 research-grade iNaturalist sightings within 25 km + 179 needs-ID sightings counted at 3% (32 of the 1,035 research-grade Morus sightings here are red mulberry) + 10 'cultivated' (planted) sightings (rule A); that is tier 4 by count (rule B). Final tier 4.
Effort
Grab & eat Shake ripe berries onto a tarp, rinse off street grime and eat; jam, pies and freezing are extra.
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

22 sources, each linked to the original.

  1. C&O Canal NHP Superintendent’s Compendium National Park ServiceBacks up: picking rules
  2. Rock Creek Park Superintendent’s Compendium National Park ServiceBacks up: picking rules
  3. Morus rubra NC State Extension Plant ToolboxBacks up: description, season, uses, safety, keeping
  4. Morus rubra (Red mulberry) Lady Bird Johnson Wildflower CenterBacks up: description, uses, safety
  5. iNaturalist research-grade observations of Morus rubra within 25 km of downtown DC iNaturalistBacks up: findability
  6. Red Mulberry Towson University Glen ArboretumBacks up: habitat, description, picking rules, uses, safety
  7. Dry or Tray Packing for Fruits National Center for Home Food Preservation (Univ. of Georgia)Backs up: keeping
  8. How Long Can I Store Frozen Foods National Center for Home Food Preservation (Univ. of Georgia)Backs up: keeping
  9. Mulberry Jelly Powdered Pectin National Center for Home Food Preservation (Univ. of Georgia)Backs up: keeping
  10. Berries-Whole (canning) National Center for Home Food Preservation (Univ. of Georgia)Backs up: keeping
  11. USDA PLANTS Database: Morus rubra (MORU2), native status USDA NRCSBacks up: native or invasive status
  12. USDA PLANTS Database: Morus alba (MOAL), native status USDA NRCSBacks up: native or invasive status
  13. Virginia Invasive Plant Species List (effective date: September 2024) Virginia Department of Conservation and Recreation, Division of Natural HeritageBacks up: native or invasive status
  14. 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
  15. 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
  16. 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
  17. Invasive Plants in the District DC Department of Energy & EnvironmentBacks up: native or invasive status
  18. Invasives in Your Woodland: White Mulberry University of Maryland ExtensionBacks up: safety details
  19. Red mulberry (Morus rubra) research-grade fruiting observations, Maryland, Virginia and DC, by week iNaturalistBacks up: season
  20. Silvics of North America: Red mulberry USDA Forest ServiceBacks up: season, habitat
  21. Wild Edibles of Missouri (Jan Phillips) Missouri Department of ConservationBacks up: season, uses, storage
  22. The Foraged Berries of June Series: How to Identify and Harvest Mulberries Natural History Society of MarylandBacks up: season, uses, storage, description, keeping