Volvariella bombycina

🏷️ Description

Also known as the Silky Rosegill, Silver-Silk Straw Mushroom, or Tree Mushroom, Volvariella bombycina is a majestic mushroom that often graces old hardwood trees with its snowy, silky cap. 🌳✨

🧬 Taxonomy & Naming: First described in 1762 as Agaricus bombycinus by Jacob Christian Schaeffer, it was reclassified in 1949 by the renowned mycologist Rolf Singer into the genus Volvariella. The name Volvariella refers to the volva—its sack-like base—while bombycina means “silky,” reflecting the mushroom’s shimmering cap.

🌱 Varieties: Var. flaviceps—a striking yellow-capped form described from Florida 🌞🍋

🌍 Habitat & Distribution

Volvariella bombycina is saprobic, feeding on decaying wood. It grows:

• On dead or wounded hardwoods, often in hollows or cracks 🪵

• Preferably on elm, beech, oak, maple, sycamore, and poplar

• Singly or in small clusters, from late spring to fall

• Found across Europe, North America, Central America, the Caribbean, Asia, Australia, and Oceania

🍽️ Edibility

🟢 Edible, but...

• Due to its rarity and thin flesh, it’s not recommended for consumption

• Has a faint horseradish-like odor and mild radish-like taste

• Culinary value: low despite being technically edible

🔎 Identification

🧢 Cap

• Size: 1.97 to 7.87 inches (5 to 20 cm)

• Shape: Ovoid to bell-shaped, later flattening

• Color: Snow white when young, may turn yellowish or brownish with age

• Texture: Covered in long, silky fibrils hanging from the margin

• Margin: Inrolled when young, not striated

🌸 Gills

• Attachment: Free from stem

• Color: White when young, turning flesh-pink with age

• Spacing: Crowded

• Texture: Fragile, with lightly scalloped edges

📏 Stem

• Size: 2.76 to 5.91 inches tall (7 to 15 cm); 0.39 to 0.98 inches thick (1 to 2.5 cm)

• Shape: Cylindrical, tapering to apex; sometimes curved

• Color: White or creamy

• Surface: Bald or finely powdery near the apex

• Ring: Absent

• Volva: Thick, bag-like at base; white, aging to ochre or brown; surface often cracked

🧬 Flesh

• Color: White

• Texture: Soft

• Reaction: Does not change when sliced

• Odor: Faintly radish-like

• Taste: Mild

🎨 Spore Print

• Color: Brownish pink

• Spores: Ellipsoid, smooth, 8–10 x 5–6 μm; thick-walled

🔬 Microscopic Features

• Spores: Inamyloid, ellipsoid, 6–9 x 3.5–5 µm

• Cystidia: Large, lageniform pleurocystidia up to 70 µm

• Pileipellis: Non-gelatinous, with long aseptate hyphae

🧪 Medicinal Properties

🛡️ Antioxidant Activity: Extracts from the mycelium and culture liquid inhibit lipid peroxidation, suggesting neuroprotective potential (Badalyan et al., 2003).

🧬 Antitumor Potential: Polysaccharides from the mycelium have shown 100% inhibition of mouse sarcoma and Ehrlich tumors at 300 mg/kg dosage (Ohtsuka et al., 1973).

Related note: Volvariella species, such as V. volvacea and V. serofila, are studied for their anti-cancer effects in human populations.

👀 Look-Alikes

1️⃣ Amanita virosa (Destroying Angel): Grows in soil, has a ring, and smooth cap

2️⃣ Volvopluteus gloiocephalus: Grows on soil, smooth cap, no shaggy hairs

3️⃣ Pluteus cervinus: No volva, brown cap, grows on wood

📉 Conservation Status

• Red-listed in several regions of Russia

• Considered rare and potentially endangered

• Monitoring of known populations is recommended

📜 Synonyms

• Agaricus bombycinus Schaeffer (1774), Fungorum qui in Bavaria et Palatinatu circa Ratisbonam, 4, p. 42, tab. 98

• Agaricus incarnatus Batsch (1783), Elenchus fungorum, p. 51

• Agaricus denudatus Batsch (1783), Elenchus fungorum, p. 53

• Amanita calyptrata Lamarck (1783), Encyclopédie méthodique, Botanique, 1, p. 105

• Agaricus giganteus Hoffmann (1789), Nomenclator fungorum, 1, p. 27

• Amanita incarnata (Batsch) Persoon (1801), Synopsis methodica fungorum, p. 248

• Pluteus bombycinus (Schaeffer) Fries (1836), Anteckningar öfver de i Sverige växande ätliga Svampar, p. 34

• Volvaria bombycina (Schaeffer) P. Kummer (1871), Der fürher in die pilzkunde, p. 99

• Volvariopsis bombycina (Schaeffer) Murrill (1911), Mycologia, 3(6), p. 281

• Volvariopsis earleae Murrill (1917), North American flora, 10(2), p. 142

• Volvaria earleae (Murrill) Murrill (1917), Mycologia, 9(3), p. 180