Toxic Mushroom Clinical Reference — Mid-Atlantic Region

Cap 5–15 cm, pale greenish-yellow to olive, smooth. Gills white, free. Stem white with a skirt-like ring (annulus) and prominent white volva (cup) at base. White spore print. Common in oak-dominated forests throughout the Mid-Atlantic; frequently found in suburban parks with planted ornamental oaks. An introduced European species now well-established in eastern North America.

White button mushrooms (Agaricus bisporus), edible puffballs, edible Amanita species. Always check for the volva (cup at stem base) — dig up the base. No edible mushroom has a volva.

Entirely white — cap (5–12 cm), gills, stem, ring, and volva all pure white. Smooth silky cap surface. Prominent white volva (cup) at stem base. White spore print. The most deadly mushroom in the Mid-Atlantic region. Widespread in deciduous and mixed forests throughout MD, VA, WV, PA, and NJ, fruiting summer through fall.

White button mushrooms, edible puffballs, edible Amanita species. Defining feature: white volva cup at stem base — always dig to expose it. The 'egg' stage before cap opens is also extremely toxic.

Small (cap 1–4 cm), honey-brown to tawny cap, smooth and hygrophanous (fading paler as it dries). Gills brown, attached. Slender stem with a ring (annulus) that may disappear with age. Grows in clusters on decaying wood (logs, stumps, buried wood). Rusty-brown spore print. Also known as Autumn Skullcap — the species G. autumnalis is now considered synonymous. Extremely common on dead hardwood throughout the Mid-Atlantic.

Honey mushrooms (Armillaria spp.), Velvet Shank (Flammulina velutipes), Pholiota species. Key distinction: Galerina has rusty-brown spore print; honey mushrooms have white spore print.

Cap 3–8 cm, reddish-brown to tawny, conical becoming umbonate. Young specimens show a cobweb-like cortina (veil) between cap margin and stem. Stem orange-brown, fibrous. Rusty-brown spore print. Found in mixed and coniferous forests, particularly in the Appalachian highlands of VA, WV, and western MD/PA. Related species C. orellanus carries identical toxicity.

Edible Cortinarius species, chanterelles, and other brown-capped woodland mushrooms. Absence of a ring combined with cobweb-like cortina remnants on the stem are diagnostic features — but the cortina disappears with age.

Cap 3–8 cm, white to pinkish-white with reddish-brown fibrous scales arranged concentrically. Center darker brown. Gills white, free. Stem white with a persistent ring (annulus). No volva. White spore print. Found in lawns, gardens, parks, grassy edges of woodland — suburban and urban settings throughout the Mid-Atlantic. Pediatric and pet ingestion risk is high due to lawn habitat.

Young Parasol mushrooms (Macrolepiota procera), edible Lepiota species, young button mushrooms. Key distinction: Lepiota brunneoincarnata is smaller (≤8 cm), with concentric reddish-brown scales and NO volva. Confirm with Poison Control for any Lepiota species ingestion.

Cap 5–12 cm, brown to grayish-brown, with numerous white warts (remnants of universal veil). Gills white, free. Stem white with a ring and small bulbous base with a rim-like volva collar. White spore print. Found in deciduous and mixed forests throughout the Mid-Atlantic, particularly under oak and beech. More potent per gram than Fly Agaric.

Edible Amanita species (A. rubescens, A. vaginata), edible button mushrooms. The white warts on a brown cap are characteristic — but warts can wash off in rain.

Cap 8–20 cm, bright red to orange-red (occasionally yellow or white), covered with white wart-like patches (universal veil remnants). Gills white, free. Stem white with a ring and bulbous base. White spore print. Common in forests throughout the Mid-Atlantic, especially under birch, spruce, and pine. The iconic 'fairy tale' mushroom.

Edible red or yellow Amanita species (rare), Caesar's mushroom (A. caesarea). The red cap with white warts is highly distinctive but warts may be washed off by rain.

Cap 5–20 cm, bright orange to orange-yellow, smooth. Gills orange, bladelike, not forking. Grows in dense clusters at the base of oaks and other hardwood trees or from buried roots. Bioluminescent gills visible in darkness (diagnostic). Orange spore print. Very common throughout the Mid-Atlantic in summer and fall.

Golden Chanterelle (Cantharellus cibarius) — the most dangerous confusion. Key distinctions: chanterelles have forked false gills (ridges), grow singly or scattered in soil; Jack-o-Lanterns have true knife-blade gills, grow in dense clusters from wood.

Cap 2–5 cm, white to cream, smooth, funnel-shaped with inrolled margin, often wavy. Gills white, crowded, running down stem (decurrent). Stem white, short. White spore print. Grows in clusters in lawns, parks, and grassy areas throughout the Mid-Atlantic. Very common in suburban lawns in autumn; easily confused with fairy ring mushroom.

Fairy ring mushroom (Marasmius oreades) — edible, also grows in lawns. Key distinction: Clitocybe dealbata has decurrent gills (running down stem) and lacks the pleasant smell of Marasmius. Any small white lawn mushroom with decurrent gills should be treated as potentially muscarine-containing.

Cap 5–15 cm, irregularly wrinkled and lobed — brain-like or saddle-shaped, reddish-brown to chestnut. Hollow or chambered when cut. Distinct from true morels (Morchella), which have a honeycomb-pitted cap. Stem whitish, chunky, chambered. Found in spring in sandy soil under conifers and near hardwood forest edges in Appalachian VA, WV, western MD, and PA. Fruiting March–May, contemporaneous with morel season. The 'brain-like' wrinkled cap (not pitted) and hollow chambers are key ID features.

True Morel (Morchella esculenta and related species) — highly prized edible. Critical distinction: true morels have a pitted honeycomb cap; false morels have a wrinkled/lobed brain-like cap. Both are hollow when cut, but false morel has irregular chambers. Always cross-section in the field.

Spherical to irregularly lobed, 3–10 cm diameter. Exterior pale yellowish-brown with coarse, scaly, mosaic-like surface. Interior flesh firm, white when young, becoming dark purple-black to black at maturity (diagnostic). No stalk (or very short). Found on woodland soil and sandy edges throughout the Mid-Atlantic. Purple-black interior distinguishes it from edible puffballs.

Giant Puffball (Calvatia gigantea), other edible puffball species. Cut puffballs in half before eating — white solid interior = safe to consider; purple/dark interior = do not eat.

Cap 6–15 cm, gray-white to silver-gray with darker gray-brown fibrous scales in concentric zones. Gills white, sinuate (notched at stem). Stem stout, white. White spore print with a distinctive mealy-farinaceous odor. Found in beech and mixed hardwood forests of the Appalachian highlands (VA, WV, western MD, PA). Also known as Dirty Tricholoma or Pardoned Knight.

Edible Tricholoma species, Knight mushroom (T. equestre — itself controversial), St. George's mushroom. Scaly gray cap pattern is relatively distinctive within the genus.

Cap 10–30 cm, white with brown shaggy scales, closely resembling the edible parasol mushroom. Gills white when young, turning distinctly green at maturity — diagnostic. Stem with a movable double ring. Spore print turns green at maturity. Grows in rings, arcs, and scattered clusters in lawns, parks, golf courses, and suburban areas throughout the entire Mid-Atlantic, spring through fall. Green gill color at maturity is the critical identifying feature.

Edible Parasol mushroom (Macrolepiota procera), Shaggy Mane (Coprinus comatus). Always check gill color before eating any large parasol-type mushroom — green gills = do not eat. Young specimens have white gills; check at full maturity.

Cap 8–20 cm, pale gray to buff or ivory, broadly convex to wavy, smooth surface with an inrolled margin. Gills initially white to pale cream, turning distinctly salmon-pink to pink at maturity as spores develop. Stem stout, white to gray. Pink spore print. Robust mushroom with an unpleasant, flour-like (mealy/farinaceous) odor. Found in mixed hardwood forests, woodland edges, and parks of the Mid-Atlantic Piedmont and Appalachian foothills, summer through fall. Often near oak and beech.

St. George's Mushroom (Calocybe gambosa), edible Tricholoma species, and Button mushroom (Agaricus bisporus) in button stage. Key distinction: always check spore print — E. sinuatum gives a distinctly pink/salmon print. Edible button mushrooms have dark brown/black spore prints. Mealy odor is an additional warning sign.

Cap 4–9 cm, convex to flat, pale buff to cream with a slightly darker ochre-brown center. Surface viscid/slimy when moist. Gills pale grayish-buff, crowded, often with distinctive water droplets (beading) on gill edges — a key identifying feature. Stem white to buff, sometimes with small white granular scales near apex. Brown spore print. Strong, unpleasant radish-like odor. Very common in woodland edges, parks, and disturbed soils throughout the Mid-Atlantic, late summer through fall. Found near oaks, alders, and various hardwoods.

Edible Portobello/Button mushroom (Agaricus bisporus), edible Tricholoma species, and various edible LBMs. Key distinction: the distinctive radish/sour odor, viscid cap, and beaded gill edges distinguish it from edible alternatives. Always take a spore print — brown print plus radish odor = high suspicion for Hebeloma.

Cap 5–15 cm, brown to ochre-brown, broadly funnel-shaped with a distinctively inrolled wavy margin. Gills yellow-brown, crowded, running down stem, bruising dark brown when pressed. Stem short, brown. Brown spore print. Found in birch and alder woodlands, often boggy areas. Common throughout the Mid-Atlantic, particularly in NJ pinelands and WV creek drainages.

Edible brown-capped woodland mushrooms. The distinctive inrolled margin and bruising yellow-brown gills are diagnostic. Previously widely consumed in Eastern Europe — Mid-Atlantic forager communities with European heritage may have childhood familiarity.

Very small (cap 0.5–2 cm), conical to bell-shaped with a distinctive nipple-like papilla at apex. Cap hygrophanous — dark brown when moist, fading to tan when dry. Margin striate. Gills gray-brown to purple-brown at maturity. Stem thin, wavy, often blue-staining when bruised. Purple-brown spore print. Found in damp pastures, meadows, and grassy areas — especially where livestock (sheep, cattle) graze. Common in NJ and MD coastal plain pastures, late summer through fall.

Edible LBMs (little brown mushrooms), Marasmius oreades, Panaeolus species (some also psilocybin-containing). Distinctive features: conical cap with papilla, blue staining when handled, purple-brown spore print.