It has a circular shape but it can also have an irregular shape, depending on the soil where it is developing. Dimensions can differ, from walnut to potatoes size. It has a warty surface with pyramidal warts 3-5 mm high. It is black and the non-ripe truffles can be reddish. It is very aromatic and has a specific flavour, not too intrusive. It is very tasty and some even call it the black sweet truffle.

This truffle was named after the Latin word brumalis, which means winter. The fruit is small in size reaching the egg size at best; of extremely black colour or brown to black with younger examples. It has an intensive flavour and pronounced taste, but less pronounced then T. melanosporum.

This truffle is very similar to the Black summer truffle. Authors describe it as a variety of the summer truffle (Tuber aestivum var. uncinatum). Nevertheless, there are some differences. Tuber aestivum var. aestivum grows in warmer parts of the Mediterranean, while Tuber aestivum var. uncinatum grows in a more fresh environment, hilly parts of the whole Europe. Tuber uncinatum grows is colder organic soils, it has darker skin and a more developed spores ornamentation, stronger taste and flavour.

CAP: 6-15 cm. In young specimen it is convex, later it spreads and becomes dented in the middle, while adult specimen have a funnel-like shape. The margin of young caps is in rolled, later it elevates but still remains slightly rolled on the margins, and on older mushrooms it is irregular and wavy. The cap skin is harsh and looks like it is covered in white hoar frost. The colour is not accentuated orange as with other milkcaps, but blurry orange, i.e. pale-orange with red, light brown or purple shades. regarding its colour it is extremely changeable milkcap so individual specimen can be lightly coloured, while others are significantly darker. On specific places it changes to green but this colour is not very accentuated (it is more accentuated on older specimen). The surface of the cap has concentric circles of darker colour.
GILLS/LEAFLETS: Dense, slightly run down the stipe, of unequal length, soft and somewhere they branch out. At first they are pale-yellow, then orange and finally red to purple with grey or brown shades. They turn dark when pressed and get a dark shade of purple, and then after some time they turn green at the point of pressure. Older gills can be green.
STIPE: up to 7 cm tall and up to 3 cm thick. Short and stubby, large and cylindrical, full when young but soon it becomes hollow. White with light brown, pink or orange shade, later they are darker with a purple shade. Usually with more or less accentuated spots or drop-like dents of dark colour (brown to red or wine-brown). At the points of pressure it turns green after some time.
FLESH: Thick, with grainy structure, friable, initially white, but soon it turns marbly red as blood and later it becomes dark purple (in the end it turns green). When cut it releases milk juice which immediately has a dark red colour as blood, and which turn brown after a few hours. The stipe's interior consists of white soft flesh. It's taste is sweet or somewhat bitter, and it has a refreshing fruity odour.

CAP: 3-15 cm. The cap is fleshy, in the beginning it is irregularly semi-circular, then irregularly convex, later it spreads and the older specimen can even be slightly indented. The cap margin in young mushrooms is turned downwards and it keeps the shape even in older mushrooms, although, usually it is wavy. It has a smooth surface, almost as fine as antelope skin, often with little humps, smaller soft bumps, dents or stripe-like ridges. It cracks open in dry seasons. The colour varies from white yellow, yellow to orange or light brown to reddish.
GILLS/LEAFLETS: It consists of spikes or needles which go down the stipe. The needles are very fragile, can be easily detached from the cap's flesh, up to 0.5 cm, the ones that go down the stipe are shorter. In the beginning they are white to creamy colour, later they become yellow orange and finally older mushrooms are reddish.
STIPE: up to 8 cm high and 4 cm thick. Mostly cylindrical, but it also forms irregular shapes, robust, hard, firm, eccentric (irregularly positioned compared to the cap), stubby, sometimes larger at the base and sometimes smaller. Smooth, sometimes cracked, white or pale-yellow, when touched or cut it becomes orange, especially at the base.
FLESH: Firm and thick but easily brake under pressure. Originally white but where it's cut it changes to yellow-orange colour. Without a particular odour, mild taste in young mushrooms, and bitter-peppery in older specimen.

CAP: 6-20 cm. When the mushroom is still young the shape is convex and conical and the highest at the centre. With age it becomes more and more indented and assumes the shape of a big funnel, the margins lift and become the highest point of the mushroom while the convex centre remains within the funnel-like cap. Sometimes the central convex shape is less developed or it does not exist at all. The cap margin is inrolled. Bare and smooth, only the margin can be slightly hairy. White to yellow brown, sometimes brown, and sometimes completely white.
GILLS/LEAFLETS: Gills are dense, bendable, sometimes wavy, mixed with shorter gills and running down the stipe. In the beginning they are white, and then become creamy coloured or have a pink shade.
STIPE: Up to 20 cm tall and 3 cm thick. Long, bulbous, cylindrical, full, larger at the base. Dry, fibrous, spongy in older specimen, the base is usually covered in white mycelic yarn. Usually of pale-brown colour, mostly similar to cap's colours.
FLESH: Firm, juicy, slightly fibrous, not very thick, except above the stipe, white. Odour and flavour are agreeable. The odour is quite complex, aromatic and fruity. Individual authors say it is reminiscent of the elder flower.

CAP: 5-15 cm. Young mushrooms are regularly semi-circular, latex convex and finally spread open and frequently irregularly curvy, with margins facing inward. Very fleshy, dry skin, not shiny, usually creamy-white colour, with dark yellow, yellow or grey shades, slightly darker in the middle (mature specimen).
GILLS/LEAFLETS: Gills are very dense and tight, white or pale creamy colour.
STALK: Up to 8 cm high and 2 cm thick. Cylindrical shape, young mushrooms have a stubby stalk, full, smooth, white or creamy colour.
FLESH: Very thick and compacted in the cap, fibrous in the Stalk, white. Taste and odour resemble flour and when the mushrooms are soaked with rain, it is even more intense.

CAP: 3-15 cm. When young it is irregularly semi-circular, then convex, then flattened, and when aged it can even be depressed. The centre of the cap can often be convex while the edges of the cap in grown specimen are curled inward. They are covered with tiny brown fluffy shells which are denser in the centre. Older fungi normally lack the shells. The colour varies; some identify it with the colour of honey, and therefore the name, honey fungus. Its colour varies from yellow to brown, frequently with shades of green or olive-green and red.
GILLS/LEAFLETS: Gills are medium dense, facing downward. Young mushrooms have a white, later it changes to yellowish or pink shade, and older specimen start to become more brownish, i.e. they look like they are brownish with spots.
STIPE: Up to 20 cm high and 2 cm thick. Sometimes slim and cylindrical, sometimes irregular and sinuous, usually bent in one part. Full, then hollow, fluffy floury on the outside, in dark yellow colour, in the top part white, and in the lower part slight thicker. It has a thick white ring in the upper part of the stalk, right beneath the gills. The ring is yellowish or brownish on the bottom side.
FLESH: White and tightly compacted in the cap, fibrous and tough on the stalk. Mild odour or slightly sour, sharp sour-bitter taste.

Perennial plant 70-150 cm tall. The stem is square, upright and not branched, with thick hairs, and usually of red-brown colour. Leaves are heart-shaped, with a petiole, serrated, green. Flowers are barely noticeable, unisex.

Perennial herbaceous plant with yellow flower heads composed of a high number of cylindrical and ligulated flowers.

The service tree is a 15-20 (30) m tall tree with a wide circular or oval crown and a 60 cm (100) diameter. The bark is ashy-grey; red-brown to dark blue, it is partly peeling off and later is becomes vertically fissured. The root system is heart-shaped with multiple and well developed taproots. Shoots are yellow-brown, bare, partially covered with a grey skin layer and sprinkled with lenticels. Short shoots are numerous and circularly wrinkled. The buds are spirally distributed around the shoots, they are 1 cm long, oval conical, with a blunt apex, covered in shells. Bud shells are wide, sticky, green, partially red with darker edges, bare and shiny. The terminal bud is bigger and longer than the lateral buds, which are leaning on the shoot. The leaf scar has a triangle to a half-moon shape with 5 marks of conducting trusses. The leaves are 15-18 cm long, unevenly downy consisting of 11 to 21 oblong and narrow leaflets, 3 - 8 cm long, with a symmetrical basis, sharply serrated margin, bare on the top side and downy on the underside but later bare and blue-green, red in autumn. Leaflets leaf out quite early. The fruits are bisexual, entomonogamous, white, 1,5 cm wide, with 35-37 flowers in corymbs. There are five petals and 20 stamens, with 5 fruit leaflets which are completely grown. It blossoms in May and June. The visible fruits are juicy, apple or pear like, up to 3 cm long, yellow-green to brown, sprinkled with lenticels, and reddish on the sunny side. They have a sour taste and only after the first frost they become brown, soft, tasty and sweet. They ripen in September and October, contain 5-6 seeds which are 7 mm long, widely oval, flat, with a sharp top, brown and more or less shiny. The seeds are dispersed by wild game, birds and rodents.

Shrub or smaller tree, 3-10 m tall. The aged bark is dark grey and vertically cracked. On young twigs you can clearly see the lenticels. Leaves are opposite, unevenly downy with 5 - 7 oval and oblong leaflets, pinnate and with a serrated margin. Flowers are white, shield-like. Fruits are black berries with red flesh which ripens in August.

Deciduous shrub which grows up to 2 m tall (without thorns). The shoots in the first year are straight or bent in an arch. In the second year they become branched. Leaves are unevenly downy, composed of 3-5 leaflets, unevenly serrated. On the top side, the leaves are light green and on the underside they are white and downy. The flowers are white and grow in racemes. The fruit is red, berry-like aggregate fruit.

Shrub which grows up to 3 m tall. Branches with strong thorns are suspended in an arch. The aged bark is brown to grey, but smooth and dark green on young shoots. The leaves are unevenly downy (5-9 leaves), oval and serrated. Flower can be individual or in a bundle of 3- 5. The fruit is cumulative - rose hip and it contains a large number of square downy nuts.

Branched deciduous shrub with thorns, 1 - 4 m tall. Short shoots end with a strong thorn. The bark is dark grey on young branches. Leaves with petioles are random, oval and serrated. The flowers are white and they develop immediately before leaves. The fruit berry is 1,5 cm big, blue to black colour and with a very sour fruit flesh.

The tree is 15-25 meters tall and the tree trunk diameter is 60 cm. The crown is in the form of an umbrella, the trunk is solid and strong, clear of branches up to a significant height compared to other species in this genus. The bark is brown-red, deeply fissured, and with time it cracks into big grey-brown panels, 2 to 10 cm thick. The root system is deep, very branched and without a taproot. The buds are cylindrical, spiked and light brown. The shells are white and fringed. The buds are not clammy. The needles have a grey-blue to light green colour. They come in bundles of two, 10 - 25 cm long and 1,5-2 mm thick. They are slightly bent and rigid, with a sharp top. They start to fall out in the third or fourth year. The flowers are unisex. Male flowers are yellow, cylindrical. Female cones develop at the top of shoots. They flower in March and April. The cones have a red-brown colour, 8-14 cm long and about 10 cm wide. They are oval and cupule shaped, and the shells have a pointed dark brown prickly apophysis and an accentuated umbo. Their reach maturity at the end of the third year and after the seeds fall out they remain attached on branches for a few more years. The pine proliferates with seeds. The seeds are large, 15 to 20 mm long and 5 to 11 mm wide. It has a narrow and short wing and a hard seed. It is brown and covered in black powder. The core is edible and is also used for the processing of edible oil. They sprout with 10 to 13 cotyledon.

Resilient perennial plant which grows from 25 cm to 1 m tall. The stem is square and branched in the lower part. It has oval, serrated, aromatic, green and deeply wrinkled leaves which keep their scent long after they are dried. They are good for the preparation of teas and medicines. The seeds are dark brown, slightly curved and small.

Low perennial shrub (50-80 cm) with many upright sprouts which are densely covered with narrow and oblong grey-green leaves with a whole edge. Flowers are borne in whorls and have blue or purple colour at the top of the sprout.

Shrub or a small tree up to 7 m tall. Mature bark peels off in stripes or shells. Needles come in whorls of three, upright. The upper side has a white band. Fruit is berry-like (female flowers), circular to oval, 6-9 mm in diameter, blue to grey to black colour.

Perennial climbing plant 5-8 m long. The wrinkled plants climb clockwise. Leaves are opposite, heart-shaped or lobed palm-like, wrinkled. Flowers are unisex, male flowers develop in a panicle, women parts flower in bracts which look like oval globes, suspended downwards and yellow-green colour. Internal shell surface has yellowish to reddish gland like shapes which gives the hop its bitter taste.

Up to 30 m tall tree with oval leaves. The flowers are monoecious; male flowers are clustered into circular catkins on long pedicles; female flowers grow in pairs but have a common cupule. The fruits are three-angled nuts which are in pairs enclosed in soft-spined cupule; known as beechnuts and used for pig fattening (pasture).

Shrub - small tree. The bark is smooth, grey to ash-like colour. The branches are separated and have thorns. Leaves have three to five lobes. The flowers grow in vertical corymbs, on twigs and have a red colour. The fruit is a red berry (one berry).

Shrub 5 to 7 m high. The bark is smooth and brown. The leaf has a short petiole; it is usually round or oval with a double serrate margin. The leaf blade is hairy, and the tree leafs out very early. The fruit is a 1,5 cm long and 2 cm wide berry of yellow-brown colour.

Perennial plant between 20 and 50 cm high. Fertile plants are produced in early spring, they are of light brown colour and non-branched. Green sterile stems start to grow after the fertile have wilted. Leaves are in whorls and they are facing upwards.

Evergreen shrub, between 30 and 60 cm high with horizontal or vertical branches. It has opposite facing leaves which are shell-like and small. The flowers are pink and they grow in long racemes. It blossoms in the end of summer. Its fruit is a dehiscent capsule.

Evergreen shrub, grows up to 5 m in height, rarely grows as a tree up to 10 (12) m high and with a 15 cm trunk diameter. The leaf has a red shaded petiole, elliptic to oval shape and toothed at the edges. It is 6-9 cm long and 2-3 cm wide. Flowers grow terminally in racemes and have a white to light pink colour. Fruits are 1,5 cm big, in the beginning they are green, then orange and finally red.

Perennial plant up to 80 cm high. The stem is upright, not branched, cylindrical in the cross-cut. Leaves have a short petiole and a spiral distribution with double or triple lobes.