Suillus granulatus

Suillus granulatus is a slippery-capped bolete of pine forests, easily recognised by its smooth, glutinous ochre-brown cap, pale yellow pores that weep milky droplets when young, and a ringless stem speckled near the apex with fine granular dots. It is edible after the slimy cap skin and tube layer are removed, though it is of modest culinary standing. As an ectomycorrhizal partner of pines it plays an important role in forest nutrient cycling.

History

The species was described in the late 18th century and its epithet granulatus, Latin for "granulated," refers to the glandular dots on the upper stem rather than the cap. Long gathered across Europe and parts of Asia, it features in central European and Russian foraging traditions, where the slimy cuticle is peeled before cooking. It is one of the better-known members of the genus Suillus, the so-called slippery jacks named for their viscid caps.

Overview

Suillus granulatus is a wild-harvested mycorrhizal fungus rather than a cultivated crop, forming symbiotic associations with pine roots that aid nutrient and water uptake for the host tree. Its commercial significance is limited next to prized boletes such as porcini, but it is collected locally where pine forests are common. Key identification features are the smooth slimy cap (it is not warty), the milky-weeping young pores, and the granular dots on the stem; the lack of a ring and the pine association help separate it from the related ringed Suillus luteus.