Leccinum aurantiacum

What You Should Know

Leccinum aurantiacum is a type of fungus found in forests of Eurasia and North America. It has a large, distinctively red cap and is also known as the red-capped scaber stalk in North America. It grows in association with various tree species, including oaks, birches, and beeches. Like many other mushrooms, Leccinum aurantiacum has potential health benefits. It is a good source of vitamins B and D, as well as minerals such as selenium and potassium.

The Leccinum genus has unique features such as a slim stem with thick scales, a hymenophore made of thin, long tubes with small pores, and white or yellowish flesh that stains when cut. All Leccinum mushrooms are mycorrhizal and edible. People enjoy eating this species and can cook it similar to other edible boletes, but its flesh turns very dark when cooked. However, like other mushrooms in the Boletaceae family, it is prone to be infested with maggots.

Other names: Red-Capped Scraber Stalk, Orange Oak Bolete, German (Espenrotkappe), Netherlands (Rosse populierboleet).

Leccinum aurantiacum Mushroom Identification

1. Cap

   The cap of Leccinum aurantiacum starts as a ball or deep dome shape, covered in a fine fur, then becomes flat with a scaly surface, ranging in color from brick red to dark brown. It can be 1.57 to 8.66 inches (4 to 22 cm) wide and has triangular flaps around the edge.

2. Tubes and Pores

   The tubes are circular, white at first and then pale brown, and end in small, angular pores that bruise pinkish-gray and then dark grey.

3. Stem

   The stem is white or buff and 1.97 to 9.84 inches (5 to 25 cm) tall, with a diameter of 0.59 to 1.97 inches (1.5 to 5 cm), covered in reddish-brown woolly scales that get darker with age.

4. Flesh

   The flesh is white when freshly cut, but can turn slightly blue and darken towards the base when handled or cut.

5. Spores

   Narrowly ellipsoidal to fusiform, 12.5-18.5 x 3.5-6µm.

6. Spore Print

   Olive brown to ocher brown.

7. Habitat

   It grows in summer and autumn scattered to gregarious in soil under pines in a forest composed largely of pines and aspens.

8. Chemical reaction

   Dirty rose-red with formalin, later turning brown-violet. With iron sulfate, the trama turns grayish-greenish and a little more greenish in previously uncolored areas.

Leccinum aurantiacum Look-Alikes

1. Leccinum versipelle

   Has however a lighter cap with more yellow hues and the roughness of the stem are dark since the beginning.

2. Leccinum vulpinum

   Occurs around pine and spruce trees. Not all authors recognize these as distinct species.

3. Leccinum rufum

   Has a less red surface of the cap and white scales on the stem.

4. Leccinum albostipitatum

   Grows with aspen and has white scales on the stem.

5. Leccinum insigne

   It is found in North America and grows in aspen or birch stands.

Leccinum aurantiacum Taxonomy and Etymology

The Orange Oak Bolete was first described by French naturalist Jean Baptiste Francois (Pierre) Bulliard in 1781, and was given the scientific name Boletus aurantiacus. The currently accepted scientific name, Leccinum aurantiacum, was published in 1821 by British mycologist Samuel Frederick Gray (1766-1828).

The generic name, Leccinum, comes from an old Italian word meaning fungus, while the specific epithet, aurantiacum, refers to the orange color of the cap.

Leccinum aurantiacum Synonyms and Varietes

• Boletus rufus Schaeffer (1774), Fungorum qui in Bavaria et Palatinatu circa Ratisbonam, 4, p. 75, tab. 103

• Boletus aurantiacus Bulliard (1784), Herbier de la France, 5, tab. 236 & tab. 489, fig. 2 (Basionyme) Sanctionnement : Fries (1821)

• Boletus leucopodius Persoon (1800) [1799], Observationes mycologicae seu descriptiones tam novorum quam notabilium fungorum, 2, p. 11

• Boletus aurantius Persoon (1801), Synopsis methodica fungorum, p. 504

• Boletus aurantius var. ß leucopodius (Persoon) Persoon (1801), Synopsis methodica fungorum, p. 504

• Boletus aurantius var. γ rufus Persoon (1801), Synopsis methodica fungorum, p. 505

• Suillus aurantiacus var. γ rufus (Persoon) Poiret (1806), in Lamarck, Encyclopédie méthodique, Botanique, 7, p. 497

• Suillus aurantiacus var. ß leucopodius (Persoon) Poiret (1806), in Lamarck, Encyclopédie méthodique, Botanique, 7, p. 497

• Suillus aurantiacus (Bulliard) Poiret (1806), in Lamarck, Encyclopédie méthodique, Botanique, 7, p. 497

• Tubiporus julii-mensis Paulet (1808) [1793], Traité des champignons, 2, p. 369, tab. 169, fig. 1-2

• Leccinum aurantiacum var. leucopodium (Persoon) Gray (1821), A natural arrangement of British plants, 1, p. 646

• Leccinum aurantiacum var. rufum (Persoon) Gray (1821), A natural arrangement of British plants, 1, p. 646

• Boletus aurantiacus var. rufus (Persoon) Mérat (1821), Nouvelle flore des environs de Paris, Edn 2, 1, p. 46

• Boletus scaber var. aurantiacus (Bulliard) Pollini (1824), Flora veronensis quam in prodomum florae italiae septentrionalis, 3, p. 603

• Boletus scaber var. rufus (Persoon) Pollini (1824), Flora veronensis quam in prodomum florae italiae septentrionalis, 3, p. 604

• Boletus viscidus var. ß aurantiacus (Bulliard) Duby (1830), Botanicon gallicum seu synopsis plantarum in flora Gallica, Edn 2, 2, p. 784

• Boletus aurantius scaber Secretan (1833), Mycographie Suisse, 3, p. 9 (nom. inval.)

• Boletus rufus scaber Secretan (1833), Mycographie Suisse, 3, p. 10 (nom. inval.)

• Gyroporus rufus (Persoon) Quélet (1886), Enchiridion fungorum in Europa media et praesertim in Gallia vigentium, p. 161

• Boletopsis rufa (Persoon) Hennings (1898), in Engler & Prantl, Die natürlichen pflanzenfamilien, 1(1**), p. 194

• Solenia rufa (Persoon) Kuntze (1898), Revisio generum plantarum, 3, p. 522

• Tubiporus rufus (Schaeffer) Ricken (1918), Vademecum für pilzfreunde, Edn 1, p. 204

• Krombholzia rufa (Persoon) E.-J. Gilbert (1931), Les livres du mycologue, tome 3. Les Bolets, p. 183

• Krombholzia aurantiaca (Bulliard) E.-J. Gilbert (1931), Les livres du mycologue, tome 3. Les Bolets, p. 118

• Krombholzia aurantiaca subsp.* rufa (Persoon) Maire (1933), Treballs del Museu nacional de ciències naturals de Barcelona, sèrie botànica, 15(2), p. 42

• Krombholziella aurantiaca (Bulliard) Maire (1937), Publicaciones del Instituto botánico, Barcelona, 3(4), p. 46

• Krombholziella aurantiaca subsp.* rufa (Persoon) Maire (1937), Publicaciones del Instituto botánico, Barcelona, 3(4), p. 46

• Trachypus aurantiacus (Bulliard) Romagnesi (1939), Revue de mycologie, Paris, 4(2), p. 141

• Boletus versipellis var. aurantiacus (Bulliard) Vassilkov (1948), Edibles and poisonous fungi of central parts of the European Districts of the URSS, p. 38

• Leccinum rufum (Persoon) Kreisel (1984), Boletus, SchrReihe, 1, p. 30

• Krombholziella rufa (Persoon) Alessio (1985), Fungi europaei, 2, Boletus, p. 474, pl. 80

• Leccinum leucopodium (Persoon) Dörfelt & G. Berg (1990), Feddes repertorium, specierum novarum regni vegetabilis, 101(9-10), p. 567

• Leccinum quercinum (Pilat) E.E. & Watling s. auct

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