Red Boletus / Leccinum aurantiacum — a mushroom of the genus Leccinum (Boletaceae family). Russian synonyms: red mushroom, red-headed mushroom, aspen mushroom, rednik.
Cap diameter 4-15 (rarely up to 30) cm, initially hemispherical with tightly adhering edge to the stem, then cushion-shaped and convex, easily detaches from the stem. Skin is red, orange or brownish-red, smooth or slightly velvety, not peelable.
Flesh is fleshy and dense, elastic in the cap, becomes softer with age; stem is longitudinally fibrous. Color when cut is white, bluish at the lower part of the stem, quickly turns blue and then black. Taste and odor are not pronounced.
Pore layer is free, initially white, then turns brownish-gray, may have olive or yellowish tint. Pores are small, angular-rounded, and surface darkens upon touch.
Stem height 5-15 cm, diameter 1.5-5 cm, solid, often widens at the base. Surface is grayish-white, covered with longitudinal fibrous scales, initially white, turning brownish with age.
Cap color depends on growing conditions: in poplar woods it has a grayish tint, in pure aspen stands — dark red, in mixed stands — orange or yellow-red.
It is established that unlike most members of the genus, Red Boletus does not have a narrow preference for mycorrhizal partners, forming symbiosis with many deciduous trees but not conifers. It is believed to most often inhabit with aspen and poplar, less commonly with willow, and may form mycorrhiza with oak, beech, walnut, and birch.
Grows in deciduous and mixed forests under young trees, in deciduous undergrowth, and is abundant in aspen thickets. In dry summers, it appears in moist, tall aspen stands. Most commonly fruits in sparse groups or singly on clearings and along forest roads, in grass.
Widespread and locally abundant throughout the forest zone of Eurasia, found in tundra among dwarf birches. Well known in European Russia, Northwest Russia, the Caucasus, Ural, Western Siberia, and the Far East. North American Red Boletus species described as L. aurantiacum are likely to belong to other species.
Season: June — October. Red Boletus fruits in three distinct layers. First layer ("earlies") — late June to early July, appears sparsely. Second layer ("harvesters") — mid-July, more abundant fruiting. Third layer ("autumnal") — mid-August to mid-September, longest and most abundant fruiting.
A well-known edible mushroom, many consider it second only to white mushroom in quality. Used fresh (boiled or fried), dried, and pickled, for salting. Usually darkens upon processing, but retains its natural appearance in marinades. To prevent or reduce darkening, soak mushrooms in a 0.5% citric acid solution before cooking.
Cultivation of Red Boletus on a garden plot: in a shaded area, area 2.5-3 m², dig 30 cm deep, and fill with nutrient mixture.
First layer: (spread on the bottom) fallen leaves, grass or wood bark (10 cm).
Second layer: forest compost or soil under trees (10 cm). Then evenly spread dry mycelium previously mixed with 1 liter of dry soil.
Third layer: plant residues, same as in the first layer, but 3 cm thick.
Fourth layer: garden soil (3-5 cm). After sowing, water using drip irrigation.
First mushrooms appear after 1.5-2 months, then every 1-1.5 weeks.
In indoor cultivation, use the same method, but plant in containers. Mycelium lives up to 5 years. Can be cultivated any time of the year.
