Cep, Penny Bun

Habitat

Boletus edulis is found on the ground in a wide variety of both deciduous and coniferous woodlands. It shows a preference for associating with beech, oak, pine, and spruce (especially Norway and Sitka spruce). Frequent in temperate areas and mountainous regions, it often grows in drier sites and is commonly found along habitat edges such as trail sides, roads, meadows, and forest openings. Fruitbodies can occur solitarily, in pairs, or scattered in larger groups, arcs, and troops. They are often initially buried beneath thick forest duff.

Photos

Appearance

Cap

Large and variable, ranging from 8–30 cm (occasionally much larger). Initially hemispherical, it becomes convex to flat or shallowly domed with age. The surface is smooth to wrinkled, dry to greasy or slightly sticky when wet. Colors range from creamy beige and tan to cinnamon-brown or rich reddish-brown, often with a paler margin.

Stem

Stout and bulky, measuring 3–25 cm long and up to 7 cm thick. It is often bulbous or club-shaped, especially when young. The surface is white to light brown and is covered in a characteristic fine, raised network of white lines (reticulation), which is most prominent on the upper half.

Tubes

Initially white and appearing 'stuffed' with cottony tissue when young, later becoming yellow-green to olive-brown. They are typically sunken or depressed around the stem attachment.

Pores

Small and round. Like the tubes, they begin white and mature to yellow, greenish-yellow, or olive-brown. They do not typically bruise blue.

Flesh

Thick, firm, and white. It does not change color when sliced or bruised, though it may occasionally show a slight reddish tint just under the cap skin.

Spore print

Olive-brown to olive-green.

Edibility

Boletus edulis is a highly prized edible species with a nutty, sweet, and pleasant flavor and firm texture. While generally safe, the tubes of older specimens can become soft and gelatinous, and large mature caps are often infested with maggots or damaged by slugs. It can be confused with the extremely bitter Tylopilus felleus, which is distinguished by its pinkish pores and spores and a dark network on the stem. Other lookalikes include various related edible boletes, but collectors should avoid any boletes with red or pink tones or those that stain blue unless they can be positively identified, as most poisonous relatives exhibit these traits.

Nutrient Source

This mushroom forms a symbiotic relationship with trees, where it exchanges nutrients it extracts from the soil for sugars produced by the tree through photosynthesis. This mutually beneficial relationship is called ectomycorrhizal. [mykoweb.eu](https://www.mykoweb.eu/fungi/boletus-edulis), [wikipedia.org](https://en.wikipedia.org/wiki/Boletus_edulis)

Common Names

Basque

onddo ona, omtozuri, onto-zuri, ontozuri, ondo, Onto Zuri, udazkeneko, onyo-zuriya, onto-zuriya, ziza lis, ondoak, onduak, onto zuri, ziza arrizcoa, zizabal

Catalan

siuró, ciureny, mullerol, ciurenc, cep, bolets de bou, Suroy, siurenys, pinotell, pinatell, bolet de fay, surenc, Siureny, sureny

Danish

Spiselig rørhat/karl johan

Dutch

Gewoon eekhoorntjesbrood

English

King Bolete, Cep, Penny Bun

Finnish

herkkutatti, koivunherkkutatti, keltaherkkutatti

French

Cèpe de Bordeaux, Cèpe citron, Cèpe des bouleaux, Cèpe, Cèpe blanc, Cèpe du Périgord

Galician

andoa, madeirudo

German

Gelber Steinpilz, Birken-Steinpilz, Steinpilz

Italian

Porcini

Northern Sami

herskogusaguoppar

Norwegian

ku-sop, bu-sop

Norwegian Bokmål

steinsopp

Norwegian Nynorsk

steinsopp

Spanish

pan de sapo, onyo-zuriya, hongo, hongo calabaza, seta de Burdeos, boleto comestible, faisán, sigro, frongo, matute, pan de risquillu, hongo blanco, Calabaza, Hongo calabaza, calabaza, hongo rubio

Swedish

karljohan, Stensopp, Karljohans svamp, karljohanssvamp, Karjohanssvamp

Welsh

Wicsen Gron

Synonyms

• Boletus betulicola
• Boletus bulbosus
• Boletus citrinus
• Boletus clavipes
• Boletus edulis
• Boletus elephantinus
• Boletus esculentus
• Boletus filiae
• Boletus persoonii
• Boletus quercicola
• Boletus slovenicus
• Boletus solidus
• Boletus venturii
• Ceriomyces crassus
• Dictyopus edulis
• Dictyopus edulis
• Gyrodon filiae
• Leccinum edule
• Leccinum elephantinum
• Suillus citrinus
• Suillus edulis
• Suillus esculentus
• Tubiporus edulis