Waxcap Fungi, Hygrocybe spp.
This has been a great autumn for fungi, with weeks of mild and damp weather following a hot and dry summer.
Particular favourites of mine are the Waxcaps, from the genus Hygrocybe. These are colourful fungi with a cool, waxen texture and often greasy or shiny caps, hence their name. The cap surface “reflects the sunlight like fine satin” (Peter Marren, “Mushrooms”, British Wildlife Publishing 2012). Waxcaps come in a variety of colours: yellows, reds, whites, orange, brown and green, and there are some sixty species in Europe.
This autumn Vanna and I have managed to photograph four species of Waxcaps in the Norwich area: the Snowy Waxcap, Hygrocybe virginea var. virginea, the Golden Waxcap, Hygrocybe chlorophana, the Parrot Waxcap, Hygrocybe psittacina var. psittacina, and the Blackening Waxcap, Hygrocybe conica. The first two species are relatively common; the second two are more localised.
Waxcaps are grassland fungi and are in decline as grasslands are ploughed up or “improved” by the addition of artificial fertilisers and, nationally, several are rare. The Waxcap Website lists two species of particular concern: Hygrocybe spadicea (Date Waxcap or Date-coloured Waxcap) and H. calyptriformis (Pink Waxcap, Pink Meadow Waxcap or Ballerina). The Conservation page on the site mentions several steps for conserving these and other grassland and churchyard fungi.
The best place to look for Waxcaps is in short grass with plenty of moss. Sheep grazed pasture is a good hunting ground, if you have any, but in this part of the world churchyards and cemeteries are the place to look. There is a key to Waxcaps on the Waxcap Website and general fungus identification guides are useful, such as Paul Sterry and Barry Hughes, “Collins Complete Guide to British Mushrooms and Toadstools“, Collins 2009. For more detailed information, there is the David Boertmann, “Fungi of Northern Europe, Volume 1: The Genus Hygrocybe“, Svampetryk 2010, although this retails at £39.50, so I don’t have a copy.
Scientists at the University of Aberystwyth measured stable isotopes of carbon and nitrogen in the soil to discover that Waxcaps feed on recalcitrant organic material (i.e. organic matter such as humus or lignin-containing material that few soil organisms can decompose), possibly recycling nitrogen from this material back into the soil system. Introducing artificial fertilisers will speed up the breakdown of this material, to the detriment of Waxcaps. The fascinating research paper by Gareth W Griffith, Gary L. Easton & Andrew W. Jones, “Ecology and Diversity of Waxcap (Hygrocybe spp.) Fungi”, can be downloaded from the Waxcap Website.
Waxcaps seem to grow where mosses occur, but the actual link (such as a symbiotic relationship) is not yet clear.