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A Forager’s Year

No. 93

Adam’s needle yucca

Yucca filamentosa

common yucca, curlyleaf yucca, spoonleaf yucca

Fruit young green seed pods (cooked; pulp scraped from the seeds)

Drawing: Britton & Brown, Illustrated Flora (1913)

Find
Common in the right habitat
Effort
Quick kitchen prep
ID risk
Beginner
Origin
native
Safety marks
  • Toxic parts
  • Cook first
Uses
  • 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: The rules are unclear. Ask the park. 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 young seed pods of Adam’s needle, a native evergreen plant of the asparagus family that forms clumps of stiff, sword-shaped leaves with sharply pointed tips and curly, thread-like filaments along the edges (NC State). In late spring and early summer it sends up a tall stalk of nodding, creamy white, bell-shaped flowers (NC State). The pods that follow are upright, oblong capsules about 2 inches long and 3/4 inch wide, often pinched in the middle, green at first and drying to brown, with many black seeds (NC State; Virginia Tech). Only yucca moths pollinate the flowers, and their caterpillars eat some of the developing seeds (NC State; Master Gardeners of Northern Virginia). Eat The Weeds says the young fruits are very bitter raw and far better roasted until tender, and the Master Gardeners of Northern Virginia say the peeled inner pulp of young green pods, with the seeds removed, is edible when properly prepared.

Safety

No poisoning from the pods is reported in the sources checked, but don’t eat them raw: Eat The Weeds says raw young yucca fruits are very bitter and give a throat or stomach ache, and the Master Gardeners of Northern Virginia say the peeled inner pulp of young green pods, with the seeds removed, is edible when properly prepared. Eat The Weeds says the plant’s natural soap is what makes yucca bitter; NC State says these saponins create soapy foam in water. NC State names the roots as the poisonous part of the closely related weakleaf yucca (saponins, low severity) and says saponins are not absorbed by the human body, so most pass without causing harm; it lists that plant’s fruit, flowers and stems as edible. The Brisbane City Council calls yucca saponins quite toxic to people but says they are poorly absorbed, so they tend to pass straight through, and that prolonged heat, such as slow baking in an oven, destroys them. The Master Gardeners of Northern Virginia say the plant’s saponins can be toxic to dogs, cats and horses and that its leaves may cause physical injury if eaten. The leaves are stiff with sharply pointed tips (NC State), so handle the plant with care; the Lady Bird Johnson Wildflower Center says sap from yucca leaves may irritate the skin of people who are sensitive or allergic to saponins. Harmless lookalikes, all planted near DC (iNaturalist): NC State says Adam’s needle is often confused with weakleaf yucca, whose dry pods NC State lists as edible; with a form of mound-lily yucca (var. tristis), whose fruit is a leathery berry up to 6 inches long that NC State lists as edible; and with red yucca, a Texas plant with red, pink or coral flowers and woody black capsules, for which NC State lists no poison.

Lookalikes

  • Weakleaf yucca Yucca flaccida harmless (may be edible)

    NC State lists it as often confused with Adam’s needle. Its leaves have flat edges with shorter filaments, usually less than 1.5 inches long, and the outer leaves bend back, giving a floppy look; its fruit is a dry, oblong capsule (NC State). NC State lists its fruit, flowers and stems as edible and only its roots as poisonous. Virginia lists it as critically imperiled; its wild Virginia stands are on limestone in the far southwest (Digital Atlas of the Virginia Flora).

  • Mound-lily yucca (incl. var. tristis) Yucca gloriosa (incl. var. tristis, also listed as Yucca recurvifolia) harmless (may be edible)

    NC State lists Yucca gloriosa var. tristis as often confused with Adam’s needle. Mound-lily yucca has stiff, straight leaves up to 2 feet long and a 6-lobed, leathery, elongated berry up to 6 inches long, produced in November and December (NC State), unlike Adam’s needle’s dry capsules about 2 inches long. NC State lists its flowers, fruits, roots and stems as edible.

  • Red yucca Hesperaloe parviflora harmless (may be edible)

    NC State lists it as often confused with Adam’s needle. Red yucca, from Texas and Mexico, has narrow blue-green leaves about 1 inch wide, red, pink or coral tubular flowers on red stalks, and woody black capsules (NC State), unlike Adam’s needle’s creamy white bells and green pods. NC State lists no poison and no edible part.

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
Beginner
Why
No toxic lookalike is named. NC State says Adam’s needle is often confused with weakleaf yucca (shorter leaf filaments, floppy outer leaves) and with a form of mound-lily yucca (a leathery berry up to 6 inches long), both of whose fruits NC State lists as edible, and with red yucca, which has red, pink or coral flowers and woody black capsules and no listed poison. The roots, the poisonous part, and the sharp leaves are obviously separate from the pods.
Handling hazards
Thorns (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
early Jul
Peak
early Jul–late Jul
Ends
mid Aug

Adam’s needle flowers from late spring into summer: the Master Gardeners of Northern Virginia give May to June, and Virginia Tech says the flowers appear once between June and August. Seed pods start to form a few weeks after the flowers (Streetcar Suburbs Publishing), and the Master Gardeners of Northern Virginia show the plant in fruit in July. The pods are green at first and dry to brown (Virginia Tech), and only young green pods are eaten (Master Gardeners of Northern Virginia). iNaturalist sightings in Maryland, Virginia and DC show flowering from late May to early July. No source gives DC dates for young pods, so the start and end are estimates: pick pods while they are still green and tender.

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 young pods for the DC area. Flowering in the region is mostly from late May to early July, pods form a few weeks after bloom, and the Northern Virginia Master Gardeners show the plant in fruit in July, so the start is placed in early July.

Peak

estimated: No source names a peak for young green pods; July is the month the Northern Virginia Master Gardeners show the plant in fruit, between the June flowering and the pods drying to brown.

End

estimated: No source says when the pods become too tough to eat. Most plants flower in June and their pods dry to brown over the summer; late-flowering plants (Virginia Tech gives flowering into August) can still carry green pods later, so the end is placed in mid August, with each pod’s greenness deciding.

Evidence

start: Master Gardeners of Northern Virginia: 'Panicles of drooping, bell-shaped flowers May–Jun'; its photo captions read 'June Clumps/Flowers, July Fruit'. Virginia Tech: 'Flowers appearing once between June and August.' Streetcar Suburbs Publishing (Hyattsville, Maryland): 'A few weeks after bloom, you’ll see large round seed pods forming on the stalk.' iNaturalist (research grade, MD, VA and DC) flowering records by week of the year: week 22: 3, week 23: 6, week 24: 1, week 25: 3, week 27: 1, week 38: 1 (about May 28 to July 8). | peak: Master Gardeners of Northern Virginia (Arlington and Alexandria), photo captions: 'June Clumps/Flowers, July Fruit'; 'Green cylindric septicidal capsules mature to brown'. | end: Virginia Tech: 'Capsules borne upright on the woody inflorescence, approximately 2 inches long, initially green and drying to brown.' and 'Flowers appearing once between June and August.' Alliance for the Chesapeake Bay: 'Blooms June - September'.

Where to look

Mostly planted in yards, gardens and public landscapes, and sometimes escaped to roadsides, old fields and old homesites; logged most in Barcroft Park and Greenbelt Park, then Bluemont and Glencarlyn parks in Arlington and Riverbend Park, all look-but-don’t-pick. Young pods are ambiguous on the C&O Canal and in Virginia state parks (ask the park first), but yucca is rarely logged there, so the sure option is yard plantings with the owner’s permission.

Habitats
street & yard trees (planted), disturbed ground & waste places, old fields & meadows
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)
  • Barcroft Park

    4 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.

  • Greenbelt Park

    4 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.

  • Bluemont Park

    3 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.

  • Glencarlyn Park

    3 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.

  • Riverbend Park

    2 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.

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

  • roast young green pods until tender, then scrape out the inside and separate it from the seeds (Eat The Weeds)
  • sweeten the roasted pulp for pies (Eat The Weeds)
  • boil the pulp dry to a paste and dry it in the oven as a sheet, to eat as is or mix with other food (Eat The Weeds)
  • harvest only young green pods; the part eaten is the peeled inner pulp with the seeds removed (Master Gardeners of Northern Virginia)

Keeping

No keeping time is published; cook them soon after picking, or dry the cooked pulp in the oven as a sheet (Eat The Weeds). There is no tested canning recipe.

Use within
within a few days
Keeps fresh
No source gives a keeping time for picked yucca pods. On the plant the pods dry and turn brown as they mature (Virginia Tech), and only young green pods are eaten (Master Gardeners of Northern Virginia), so cook them soon after picking.
Keeping basis
specific to this plant

Ways to keep it

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

    Eat The Weeds: boil the roasted pulp dry to a paste and dry it in the oven as a sheet; it can be eaten as is or mixed with other food. No tested canning recipe exists for yucca pods.

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 in the Coastal Plain of Delaware and Maryland and, infrequently, in Virginia’s Coastal Plain; around DC it grows mainly where planted or where it has spread from planting, and its range in Virginia has probably increased dramatically as a result of cultivation (Master Gardeners of Northern Virginia; Digital Atlas of the Virginia Flora).

Origin
native
Native range
southeastern United States
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 377 = 64 research-grade iNaturalist sightings within 25 km + 84 needs-ID sightings counted at 96% (64 of the 67 research-grade Yucca sightings here are Adam’s needle) + 233 'cultivated' (planted) sightings (rule A); that is tier 2 by count (rule B). Rule D does not apply: the Master Gardeners of Northern Virginia say it is "absent in Arlington & Loudoun counties and in DC" and, in Virginia, "infrequent in the Coastal Plain as a native", but these describe the counties where the state atlas records it and its native stands, not a rare plant, and the Digital Atlas of the Virginia Flora, of equal standing, calls it "Frequent throughout" Virginia. Final tier 2.
Effort
Quick kitchen prep Roast young green pods until tender, then scrape the pulp away from the seeds; making pie filling or oven-dried sheets of pulp is 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

26 sources, each linked to the original.

  1. Rock Creek Park Superintendent’s Compendium National Park ServiceBacks up: picking rules
  2. C&O Canal NHP Superintendent’s Compendium, effective September 11, 2026 National Park Service, Chesapeake and Ohio Canal NHPBacks up: picking rules
  3. 4VAC5-30-50. Flowers, plants, minerals, etc. Virginia Law Library (law.lis.virginia.gov)Backs up: picking rules
  4. 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
  5. Yucca filamentosa (Adam’s Needle Yucca, Curlyleaf Yucca, Spoonleaf Yucca) NC State Extension Gardener Plant ToolboxBacks up: description, habitat, safety, native or invasive status
  6. Yucca filamentosa (dendrology fact sheet) Virginia Tech Department of Forest Resources and Environmental ConservationBacks up: description, season, storage, keeping
  7. Yucca’s Not Yucky (Yucca, Yuca: Which is Edible?) (Green Deane) Eat The WeedsBacks up: description, uses, safety, storage, keeping
  8. Tried and True Native Plant Selections for the Mid-Atlantic: Yucca filamentosa (Common Yucca, Adam’s Needle), fact sheet (2026) Master Gardeners of Northern Virginia (Virginia Cooperative Extension)Backs up: description, uses, season, habitat, safety, picking rules, storage, native or invasive status, findability, keeping
  9. iNaturalist research-grade observations of Yucca filamentosa within 25 km of downtown DC iNaturalistBacks up: findability
  10. Yucca filamentosa L. (Common Yucca, Adam’s Needle) Digital Atlas of the Virginia Flora (Virginia Botanical Associates)Backs up: habitat, findability, native or invasive status
  11. Yucca filamentosa, Adam’s needle (Native Plant Center) Alliance for the Chesapeake BayBacks up: habitat, season
  12. USDA PLANTS Database: Yucca filamentosa (YUFI), 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. Weed Identification Tool: Yucca (Yucca aloifolia) Brisbane City Council (Queensland, Australia)Backs up: safety
  19. Mr. Smarty Plants: Toxicity of Yucca leaves (August 19, 2009) Lady Bird Johnson Wildflower Center (University of Texas at Austin)Backs up: safety
  20. Yucca flaccida Haworth (Weakleaf Yucca) Digital Atlas of the Virginia Flora (Virginia Botanical Associates)Backs up: safety details
  21. Natural Heritage Resources of Virginia: Rare Plants (Natural Heritage Rare Species Lists 2026-Fall) Virginia Department of Conservation and Recreation, Division of Natural HeritageBacks up: safety details
  22. Yucca flaccida (Adam’s Needle, Flaccid Leaf Yucca) NC State Extension Gardener Plant ToolboxBacks up: safety, safety details
  23. Yucca gloriosa (Mound Lily Yucca) NC State Extension Gardener Plant ToolboxBacks up: safety, safety details
  24. Hesperaloe parviflora (Red Yucca) NC State Extension Gardener Plant ToolboxBacks up: safety, safety details
  25. Rewilding Route 1: Strange (bud) fellows (Rick Borchelt, May 9, 2024) Streetcar Suburbs Publishing (Hyattsville, Maryland)Backs up: season
  26. Research-grade observations of Adam’s needle (Yucca filamentosa) in Maryland, Virginia and DC, by week (flowering) iNaturalistBacks up: season