A thermophile fungus growing mainly under oaks, the Boletus aereus is one of Slovakia's more important mushrooms. It is particularly abundant in the following areas: the southern part of the Strážov and Štiavnica hills, the Ipeľ and Bodva Uplands, the Krupina Plateau, the Lučenec, Rimava, Rožňava and Košice basins, the Cerová and Revúca Uplands, the Slovak Karst and the Zemplín Hills. Most habitats are to be found at between 200 and 400 metres above sea-level.
The mushroom, which favours well-lit and warm locations, grows from the end of May to the beginning of October and culminates in waves at the turn of June and July and of August and September.
The Boletus aereus is an excellent and very popular edible mushroom whose aroma is most in evidence when the sporophores have been dried.
The morel (morchella esculenta) is one of the most widely consumed of spring mushrooms. Found throughout the whole of Slovakia from lowlands to the submontane vegetation belt and, albeit only rarely, in higher reaches, it grows in well-lit fringes of deciduous forests and in meadows, shrubbery and orchards. The morel favours moist, clayey soil on either basic or acidic substrate. Its presence culminates usually in the latter half of April in the warmer parts of Slovakia and in mid-May in colder climes. A characteristic feature of morels is that they appear in the same place for many years. The fruiting period, however, normally lasts only two weeks and the more abundant habitats occur for the most part as very small, isolated areas. As far back as the Middle Ages the morel was a staple part of the our ancestors' diet, its popularity extending to the kitchens of the nobility. The duty to pick the fungus for manorial lords appears among many records of peasant or villein service. The morel's fine flavour can be appreciated both fresh and dried. The commemorative stamp features the so-called "Czech morel", again an excellent edible fungus. Generally considered a rarity in Europe, it nevertheless grows in great abundance in Slovakia, particularly in woods and shrubbery in the south. It is our first spring mushroom that can be put to culinary use.
The Catathelasma imperiale is a variety of fungus which used to be very common in what is now Slovakia and was sold in considerable quantity at markets. Its firm, white aromatic stipe, which is rarely attacked by insect larvae, made it a favourite among practical mushroom-gatherers, who often rated it on a par with the Boletus reticulatus. At present the Catathelasma imperiale is disappearing from our forests at an alarming rate and is encountered with regularity only in some localities in Orava, the Liptov basin and Spišská Magura. The Catathelasma imperiale is to be found scattered along the entire temperate zone of the northern hemisphere and in most countries of northern and central Europe, though never in great quantity. It grows in upland coniferous forests, particularly those on limestone, where it forms a mycorrhizal association with pine and, to some extent, with fir and juniper. The so-called fairy ring mushroom depicted on the stamp is a small, unspectacular mushroom which grows in meadows and pastures, often in the rings which give it its name. It has a pleasant aroma and taste and is used predominantly for soups.
The design on the commemorative stamp shows another flavoursome, but little gathered, mushroom, Gomphidius glutinosus, which is to be found in abundance under pine in the autumn months.