#21 Suillus granulatus

With the help of other amateur fungi enthusiasts, I have established that the most recognisable physical difference (for amateurs) between Suillus granulatus and Suillus luteus is the absence or presence of a ring or annulus.

In some fungus species a partial veil initially covers the pores or gills. As the fruit body expands and matures, the partial veil usually breaks to form a 'ring' on the stem. Suillus granulatus does not have remnants of a ring, whereas Suillus luteus usually does. This feature makes it a little easier to distinguish between these two boletes that are otherwise very similar in appearance, both of which are from family Suillaceae.

Yellow pores of Suillus granulatus

Suillus granulatus is mychorrhizal with various exotic conifers, meaning that it forms a symbiotic relationship with pines. Both Suillus granulatus and Suillus luteus were introduced to Australia from Europe with exotic trees.

A bolete is a fungus with a cap and stalk that has a series of small pores on the underside of the cap, instead of gills. The pores may be either round or angular. The spores are formed inside the pores and they drop out of the pores when mature.

Pores are the 'mouths' or openings of tubes. A cross-section of a bolete shows the narrow tubes compacted.

Caps of Suillus granulatus are convex (dome-shaped) at first, becoming broardly convex, then flattening, sometimes disfiguring. The cap is viscid (sticky or slimy), although, in my limited experience, not always. There should be no remnants of partial veil on the rim of the cap or on the stem.

Stem is white, speckled with brown, and is not always centrally placed. Pores are yellow, aging to a dull yellow, and flesh is white to pale yellow. Spore print is yellow-brown.

Suillus granulatus stem is sometimes off-centre

Caps can turn up with age

My sightings of Suillus granulatus

[This will be updated with new sightings]

Greta, NSW - under exotic pines - Mar, May.

Hanging Rock, NSW - on the edge of pine plantation - Apr.

Suillus granulatus on the edge of pine plantation at Hanging Rock. Note the collapsed fungus (front right) - these boletes, like many, collapse and decay quickly and are often infested with magots.