Suillus grevillei

The genus Suillus

The genus Suillus belongs to the order Boletales, has distinctive features that are shared by many of the different Suillus species. These middle-sized fungi have a firm, cylindrical stem that often has a ring resulting from the remains from the partial vail (the membrane that protects the spore producing pores under the cap as the mushroom develops). The caps of most species are slimy or slippery, especially after rain, and have pore like structures on the underside which range in colour from yellow, light orange to olive green or even grey shades. The spore colour of this genus is usually cinnamon brown to chocolate brown. The name ‘Suillus’ comes from the Latin noun sus meaning pig. Hence, Suillus means ‘of pigs’ and refers to its greasy cap which is shared by the different Suillus species.

Suillus grevillei

A fairly common species, often growing in troops, and one of the earlier fruiting species of Suillus in summer and then throughout autumn in grasslands and parks. Spotting this fungus, you will recognise that a larch tree won’t be far away, hence the common name Larch Bolete. The fungi, just like all Boletes, are ectomycorrhizal meaning obligately associated with a plant (mostly tree species). The fungus is named after the Scottish mycologist and botanist Robert Kaye Grevillei (1794-1866).

The cap is between 3-10 cm in diameter and varies between bright yellow, yellow orange to golden brown. It is slimy under moist conditions and shiny and smooth when it’s dry. A nice field characteristic is the woolly yellowish veil that covers the lemon-yellow pores of young fruit bodies. The stem varies between 6-12 cm in length and 1-2.5 cm in thickness and possesses a yellow colour with brownish fibrils. Once the veil ruptures from the cap edge it remains as a prominent thick ring zone near the top of the stem. The flesh of S. grevillei is vivid yellow and appears pinkish-violet when first cut. The smell is pleasantly fruity, the taste mild sometimes slightly sour. The species belongs to the edible fungi, however its taste is not of the most culinary order.

Season:

Suillus grevillei can be found from late summer to autumn.

Habitat:

Associated with larch.

Distribution:

It is a very common species throughout Scotland.

Similar species

Suillus grevillei photos by D. Genney

Suillus grevillei distribution map

The other species of Suillus are relatively easy to differentiate from S. luteus. See their profiles in the

Fungus of the Month index page.

There are two other main groups of fungi that have a central stem and pores instead of gills:

Boletus species have dry caps and normally a network pattern on stem e.g. Cep.

Leccinum species have stems that are covered in small scales of varying colours, dry caps and associated with broadleaf trees e.g. Orange Birch Bolete.

The National Biodiversity Network Atlas records from all available datasets are shown on the above map (see terms and conditions at http://data.nbn.org.uk). Data providers and the NBN Trust bear no responsibility for any further analysis or interpretation of the information in the map.

Note also that additional records may be available on the Association of British Fungus Groups CATE2 database, but these are not available via the NBN Gateway.

Please remember to submit your records to your local recording group or via the Scottish Fungi online recording form.

By Peggy Ehrlich and Dave Genney

September 2016