Laetiporus sulphureus (Chicken-of-the-Woods)

Laetiporus sulphureus is a wood decay (saprotrophic) fungus causing brown rot often on oak and other hardwood trees, such as beech, chestnut, and cherry. It has also been reported from yew trees. Saprotrophic fungi decay dead stumps and logs and act as important recyclers of nutrients and minerals which can then be re-used by other organisms. Laetiporus sulphureus, however can colonize both dead and living trees acting as a weak pathogen on living trees. Wood is primarily composed of cellulose (long chains of sugars) and lignin (one of nature’s most complex substances). Brown rot is characterised by the brown colour of the wood which is a result of the fungus degrading the cellulose and similar wood components but leaving the lignin untouched.

Laetiporus sulphureus is said to be one of the easy to recognise fungi. With its large size and striking sulphur-yellow to orange colour it is hard to miss, especially as a single tree can often produces several kilos of this fungus. Some people say that the fungus possesses a remarkably similar texture and taste to chicken, which is why it is also commonly known by the name Chicken-of-the-Woods. It is advised to just collect young specimens, being bright yellow to orange, as older specimens, being dull yellow to white, become rather woody with age and often developing an acrid flavour. The Chicken-of-the-wood is a fast growing fungus which, if just the outer edges (about 5 cm) are collected/cut, recovers quickly and allows for second harvest later during the season. However, around 20% of people show sensitivity to this mushroom becoming ill quickly after consumption. For this reason it is advised to only consume a small portion the first time it is tried. In addition, fruit bodies growing on yew trees are best avoided as the conifer contains itself toxins which apparently are taken up by the fungus.

The wavy-edged cap of the fruit body ranges 5 to 30 cm across, up to 20 cm deep and up to 3 cm thick, growing in a cluster that can reach up to 75 cm across. The Chicken-of-the-Woods belongs to the family of the Polyporaceae, and as suggested in the name Laetiporus meaning ‘with bright pores’ has small, pale yellow tubes, rather than the more commonly encountered gills, underneath the fruit bodies. The fruit body grows directly out of the tree trunk and therefore does not possess a stem. The flesh of the fruit body is thick, watery and soft when young and turns into a tough and woody like structure that becomes crumbly and cheese-like with age.

Mycologists in the United States of America have identified certain variations within the Laetiporus species according to pore colour, growing position in the tree, geographical distribution and host trees. Molecular studies confirmed that there are different Laetiporus species present such as Laetiporus cincinnatus. However, Laetiporus sulphureus is the only Laetiporus species known for the UK. A similar looking species present in the UK is Meripilus gigantus. This species is rather variable in its appearance however its main difference is the pore surface which immediately stains brown to black when bruised.

Season

Laetiporus sulphureus is most commonly found from August till October but occasionally occurs as early as May.

Habitat

Often found in tiers growing around living or dead tree stumps commonly with oak and other hardwoods.

Distribution

The species is known to be widespread and common throughout Scotland and the north temperate zones.

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

Photos by Neville Kilkenny and Andy Taylor

By Peggy Ehrlich and Andy Taylor

Laetiporus sulphureus

Laetiporus sulphureus

Laetiporus sulphureus distribution map

The National Biodiversity Network Gateway records from FRDBI andHBRG datasets are shown on the above map but note that as of May 2015 the FRDBI has not been updated on the gateway since 2007. More recent records from other sources may be available via the Gateway (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.