TUBER AESTIVUM Vittadini
Monographia Tuberacearum 38, Tab. II fig. IV (1831)
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Synonyms:
Tuber albidum Cesalpino (1583), De plantis libri XVI 616 sensu Fries (1823)
Tuber cibarium Sowerby (1797), Colored figures of English fungi or mushrooms, London, t. 309
Tuber nigrum Allioni (1785), Flora pedemontana 2, 366 sensu Vittadini (1831)
Tuber albidum Cesalpino: Fries (1823), Systema Mycologicum 2, Pt. II: 291
Tuber blotii Deslongchamps (1824), Mém. Soc. Linn. Calvad. 47, f. 1-3
Tuber uncinatum Chatin, C. R. hebdom. Acad. Sciences 104: 1132 (1887); La truffe 55, t. 7 f. 1 a-e
Macroscopic characters:
Ascomata: hypogeous, subglobose, 2-9 cm, blackish-brown to black, conspicuously warted. Warts 3-12 mm across, pyramidal, 4-6-sided, often depressed at the apex, vertically fissured, usually with fine horizontal striae.
Gleba: firm, solid, white when immature, becoming light brown, dark brown at maturity, marbled with numerous, thin, white, meandering, branching veins that do not change colour when exposed to the air.
Odour: slight and pleasant at first, like roasted malt, becoming strong, seaweed-like with age.
Taste: mild, reminiscent of nuts (walnuts, hazelnuts)
Habitat
Although you can also find Tuber aestivum in the same places as Tuber melanosporum (well drained, airated calcareous soils with high porosity), Tuber aestivum grows in more compact and clayey soils, usually in sunny places (unlike Tuber uncinatum always in shady places). Tuber aestivum inhibits plants growing and makes more conspicuous "burns" than Tuber melanosporum. Black summer truffles grow quite superficial and we can detect their presence through the cracks in the soil. They are sometimes found under leaf litter. Usually they are harvested from May to July, but we can find them until December if moisture conditions are suitable. Tuber aestivum are associated with the roots of several trees: oaks (Quercus), beeches (Fagus sylvatica), poplars (Populus), hazels (Corylus), pines (Pinus) and lindens (Tilia).
Notes:
Molecular analysis showed no differences between Tuber aestivum and Tuber uncinatum. Differences in taste, odor and spore morphology are because of ecological factors.
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Microscopic characters:
Asci: globose to subglobose, sessile or short-stalked, 60-110 x 50-70 µm, 1-6-spored (usually 3-4-spored).
Ascospores: 20-45 x 18-35 µm excluding ornament, size variable depending on number of spores in the ascus, Q range = 1,21-1,37, ellipsoid to subglobose, yellow, translucent, ornamented with a coarse irregular reticulum 3-5 µm high, meshes variable, usually 3-5 across width of spore and often with incomplete secondary crests inside.
Peridium: pseudoparenchymatous
 | Antonio Rodríguez trufamania@gmail.com antonio@trufamania.com |