Hymenopellis radicata
🏷️ Description
If you love stumbling across unusual and graceful mushrooms during woodland walks, you might meet Hymenopellis radicata — better known by its charming common names, The Rooting Shank or The Deep Root Mushroom. This distinctive fungus isn’t just another cap-and-stem mushroom — it literally digs deep, with a long, root-like extension of its stem plunging into buried wood beneath the forest floor. Let’s get to know this fascinating species! 👇
💡 Fun Fact: The long, buried stem extension often makes as much of the mushroom hidden beneath the soil as what you see above ground! It persistently grows downwards until it finds dead wood to feed on — a literal underground explorer.
🍽️ Edibility
Technically edible but not highly valued. It’s mild to slightly fruity in scent and taste, sometimes with a faint bitterness that disappears upon cooking. However, it’s seldom found in large numbers, making it a forager’s curiosity rather than a basket filler.
🔎 Identification
🧢 Cap
-
Size: 1.57 to 9.84 inches (4 to 25 cm) in diameter.
-
Shape: Starts convex or bell-shaped, becoming flatter with a broad, low central bump (umbo).
-
Color: Ranges from pale grey-brown to hazel-brown or mid-brown, often darker at the center.
-
Surface: Sticky or slimy when moist, becoming silky with radial wrinkles as it dries.
🥩 Flesh
-
Color: White to off-white.
-
Texture: Thin, soft, watery in the cap; fibrous and tough in the stem.
-
Odor & Taste: Neutral to slightly fruity, with a mild flavor.
🌿 Gills
-
Attachment: Adnate (broadly attached) with a slight decurrent tooth, or occasionally appearing almost free.
-
Color: White to pale cream, darkening at the edges with age.
-
Spacing: Distant, interspersed with numerous shorter gills (lamellulae).
-
Special Feature: In older specimens, edges may become finely wavy, serrated, or even spotted brown.
📏 Stem
-
Size: 2.36 to 7.87 (occasionally up to 9.84) inches (6 to 20 cm) long; 0.2 to 0.59 inches (0.5 to 1.5 cm) in diameter.
-
Shape: Slender, cylindrical, sometimes twisted, with a deeply rooted, elongated base resembling a ‘taproot’ plunging several inches into buried wood.
-
Color: White near the apex, darkening to brown towards the base.
-
Surface: Finely floccose (powdery) and longitudinally fibrillar (thread-like grooves).
-
Ring: Absent.
🔬 Microscopic Features
-
Spore Print: White.
-
Spores: 0.47 to 0.75 x 0.31 to 0.55 inches (12–19 x 8–14 μm), broadly ellipsoidal to lemon-shaped, smooth, with a germ pore. Inamyloid (non-staining in iodine).
-
Basidia: 4-spored, 1.77 to 2.16 x 0.39 to 0.59 inches (45–55 x 10–15 μm), clavate (club-shaped), with clamp connections.
-
Cheilocystidia: 2.36 to 4.33 x 0.47 to 1.38 inches (60–110 × 12–35 μm), broadly clavate or ventricose (swollen).
-
Pleurocystidia: 2.36 to 4.72 x 0.87 to 1.38 inches (60–120 × 22–35 μm), similarly swollen and blunt-ended.
🌳 Habitat & Ecology
Hymenopellis radicata is a saprobic species, meaning it feeds on decaying wood, particularly rotting stumps and buried hardwood. It’s commonly associated with broadleaf trees like beech, but occasionally turns up under conifers as well.
-
📅 Season: Early summer to late autumn.
-
🌍 Distribution: Widespread in Britain, Ireland, most of mainland Europe, and North America.
-
🧬 Ecological Role: An early-fruiting wood rotter, contributing to woodland nutrient cycles by breaking down dead wood.
👀 Look-Alikes
-
Hydropus subalpinus
The rare mushroom, lignicolous too, with smaller dimensions, the cuticle of the cap not wrinkled and the umbo is more acute and the stem is not rooting.
-
Has velvety stem and cap.
-
Pluteus genus
But a spore print (spores are pink in mass for Pluteus) would resolve any doubt.
📜 Synonyms
Agaricus clypeatus Hudson (1778)
Agaricus umbraculum Batsch (1783)
Agaricus radicatus Relhan (1786)
Agaricus incarnatus Relhan (1788)
Agaricus longipes Bulliard (1791)
Agaricus macrorhizus Persoon (1796)
Agaricus radicatus var. ß liber Schumacher (1803)
Gymnopus longipes (Bulliard) Roussel (1806)
Hypophyllum radicatomammosus Paulet (1808)
Gymnopus radicatus (Relhan) Gray (1821)
Agaricus phrygius Wallroth (1833)
Collybia radicata (Relhan) P. Kummer (1871)
Mucidula radicata (Relhan) Boursier (1926)
Oudemansiella radicata (Relhan) Singer (1936)
Collybia radicata f. albida Wichanský (1960)
Xerula radicata (Relhan) Dörfelt (1975)