Boletus betulicola

The main look-alike that is dangerous for its taste (not its toxicity) is the bile bolete, or bitter bolete (Tylopilus felleus): it has pinkish pores, a dark contrasting net on the stem and unbearably bitter flesh that ruins the whole dish. The birch porcini has white-to-yellowish pores, a pale net and a mild taste. If you touch your tongue to the cut flesh and taste bitterness — it's not a porcini, put it back.

No. True porcini stays white when cut — it does not turn blue, red or dark. If your "porcini" turns noticeably blue within a few minutes, you are looking at a different bolete (for example, a bluing bolete). That isn't deadly, but for confident porcini identification, flesh that keeps its color is a must-have feature.

In light birch and mixed forests: Polissia (Volyn, Rivne, Zhytomyr, Chernihiv and Sumy regions), the western oblasts and the Carpathian foothills. It loves forest edges, sun-warmed clearings, path verges and young clearings with birch. It often hides in grass and under leaves — scan the ground carefully, without hurrying.

Above all with birch (Betula) — hence the name. In mixed forests it may also partner with pine and spruce growing alongside birches. In pure conifer forests without birch, its place is taken by other forms of porcini — the pine bolete (Boletus pinophilus) or the summer bolete (Boletus reticulatus).

From June to October, with the main flush in late summer and early autumn after warm rains. The first scattered mushrooms appear as early as midsummer, and the cleanest, firmest ones come in the later autumn flushes, when the heat breaks and there are fewer insects.

Yes. On warm summer days porcini are very quickly colonized by insect larvae, so summer specimens are often wormy within a day or two. In autumn, in the cool, the mushrooms stay clean much longer — which is why experienced foragers value the autumn flush most of all.

These are close forms of a single complex; the difference lies mainly in the partner tree and the shade. The pine bolete (Boletus pinophilus) is darker, wine-chestnut, and grows with pine; the summer bolete (Boletus reticulatus) has a more pronounced net and favors oaks and warm forests. The birch form is the palest, pale hazel, and always near birch.

The brown birch bolete (Leccinum scabrum) also grows with birch, but it has a thin, slender stem covered in dark dotted scales, and softer, watery flesh that often turns pinkish or grayish when cut. The birch porcini has a thick stem with a delicate pale net, and its flesh is firm and unchanging. Both are edible, so a mix-up isn't dangerous — only a culinary one.