Postia bluish-gray

Postia bluish-gray (Postia caesia) Postia bluish-gray (Postia caesia) Postia bluish-gray (Postia caesia)

Postia bluish-gray (Postia caesia)


  • Department: Basidiomycota (Basidiomycetes)
  • Subdivision: Agaricomycotina (Agaricomycetes)
  • Class: Agaricomycetes (Agaricomycetes)
  • Subclass: Incertae sedis (undefined)
  • Order: Polyporales
  • Family: Fomitopsidaceae (Fomitopsis)
  • Genus: Postia (Postia)
  • Species: Postia caesia (Postia bluish-gray)
    Other names for the mushroom:
  • Oligoporus bluish gray
  • Postia bluish-gray
  • Postia gray-blue

Other names:

  • Oligoporus bluish gray;
  • Postia is bluish-gray;
  • The post is gray-blue;
  • Bjerkandera caesia;
  • Boletus caesius;
  • Oligoporus caesius;
  • Polyporus caesiocoloratus;
  • Polyporus ciliatulus;
  • Tyromyces caesius;
  • Leptoporus caesius;
  • Polyporus caesius;
  • Polystictus caesius;

Postia bluish-gray (Postia caesia)

External description

The fruiting bodies of the bluish-gray postia consist of a cap and a leg. The stem is very small, sessile, and the fruit body is half-shaped. The postia is bluish-gray, characterized by a wide spreading part, fleshy and soft structure.

The top of the hat is white, with small bluish spots in the form of spots. If you press hard on the surface of the fruiting body, the pulp changes its color to a more intense one. In immature mushrooms, the skin is covered with a bristle edging, but as the mushrooms mature, it becomes bare. The pulp of this type of mushroom is very soft, white in color; under the influence of air it becomes blue, greenish or grayish. The taste of the bluish-gray post is insipid, the pulp is characterized by a barely noticeable aroma.

The hymenophore of the fungus is represented by a tubular type, has a grayish, bluish or white color, which becomes more intense and saturated with mechanical action. The pores are characterized by their angularity and large size, and in mature mushrooms they acquire an irregular shape. The tubules of the hymenophore are long, serrated and very uneven edges. Initially, the color of the tubes is whitish, and then it becomes fawn with a bluish tint. If you press on the surface of the tube, then its color changes, darkens to bluish-gray.

The length of the cap in a bluish-gray post varies within 6 cm, and its width is about 3-4 cm. In such mushrooms, the cap often grows together with the leg sideways, has a fan-shaped shape, is covered with visible villi on top, fibrous. The color of the mushroom cap is more often grayish-blue-green, sometimes lighter along the edges, having yellowish tints.

Season and habitat of the mushroom

You can meet the bluish-gray posture in the summer and autumn months (from July to November), mainly on the stumps of deciduous and coniferous trees, on tree trunks and dead branches. The fungus is found infrequently, mainly in small groups. You can see the bluish-gray posttia on dying wood of willow, alder, hazel, beech, fir, spruce and larch.


There are no toxic and poisonous substances in the fruiting bodies of bluish-gray Postia, but this type of mushroom is very tough, so many mushroom pickers say that they are inedible.

Similar types and differences from them

In mushroom growing, there are several closely related varieties with bluish-gray posture, differing in ecology and some microscopic features. For example, Postia bluish-gray has a difference in that the fruit bodies of the fungus do not turn blue when touched. This mushroom can also be confused with alder post. True, the latter differs in the place of growth, and is found mainly on alder wood.

Other information about the mushroom

The first description for the postia bluish gray was by Heinrich Adolf Schrader. The scientist made it in 1794, in a group with other mushrooms that have a tubular hymenophore. In 1821, another scientist – E.M. Fries transferred the bluish-gray posture to another genus – tubular tree fungi, narrower in structure. And only in 1881, Peter Adolf Carsten transferred the mushrooms of this species to the genus Postia.

Postia bluish-gray (Postia caesia) Postia bluish-gray (Postia caesia) Postia bluish-gray (Postia caesia)

Photo of the Postia mushroom bluish-gray from the questions in recognition:

Postia caesia - Postia bluish-gray 2017.02.25

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Hunting, Fishing and Mushrooms: a magazine for hunters and fishers.
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