Hertfordshire fungi observations 2022- Kerry Robinson

Winter is the time of year I reflect on the autumn foray lists and as I suspected it was a poor season for mycorrhizal fungi. It is now over forty years since I started looking and recording fungi in my area.

The few remnants of ancient woodland were once covered in troops of fruitbodies. Now like all other groups in the natural world they have declined. Climate change has seen increasingly dry springs and high temperatures in summer. Autumn records have recently been represented by single specimens, instead of quantity, so total bio diversity still appears good. The Herts and Beds group has also increased its knowledge of other groups of fungi. Woods are under increasing pressure from the large amount of people using them and foragers emulating TV chefs and over collecting plants and edible fungi. The photograph taken in the autumn of 1982 of Clitocybe nebularis, the Clouded Agaric shows how abundant common species used to be. (fig 1) I haven’t seen a sight like this for over twenty years.

Fig 1 ‘Clitocybe nebularis’Berkhampstead – October 1982

On a more positive note there were a few new county records and some rarely recorded species. In my first weeks of retirement I spent some time in my local wood, the Weston Hills, Baldock. Here I was rewarded with four interesting records, two new to the county. Firstly Hemimycena mauretanica var mauretanica, a small all white Mycena like species, with very few gills growing on an old fallen Hawthorn leaf. (fig 2) My second find was a Resupinatus species. Its small ear shaped caps were grey and covered in white sugar like granules, the gills were few and distant, also grey in colour. Peter Orton had named a species called Resupinatus kavinnii which I thought it might be, so I sent it to Alick Henrici for a second opinion. The problems then started. He checked at Kew on some recent papers on the genus and found some species had been reassigned, but mine didn’t match any of those. For the time being I have called it Resupinatus cf kavinii, hoping DNA will sort it out. (fig 3).

Fig 2 ‘Hemimycena mauretanica var mauretanic’

Fig 3 ‘Resupinatus cf 

Fig 3a ‘Resupinatus cf kavinii’ kavinii’

On another outing I was searching old very wet Silverweed leaves, hoping to find Gnomonia comari which I didn’t. What I did find were some whitish cream cups around 0.3mm big with long white hairs. Under the microscope I soon realised this was a basidiomycete. The hairs had long whip like ends and the middles were covered in crystals. Spores were 7-8×4.5-5um, this fitted well with Flagelloscypha orthospora.

Lastly from the Weston Hills was Tomentella umbrinospora a lovely orange/brown corticioid growing on an old Beech log. I had the first British record for this in 1995 from Royston Heath, Fox Covert reserve, both records from the same type of habitat Beech trees on calcareous soil.

A favourite wood of mine is Astonbury woods, Stevenage it has a good variety of habitats and never fails to yield something interesting. A jelly fungus with a pinkish/grey tinge formed a thin covering on a fallen deciduous branch, this was Saccosoma farinacea (=Helicogloea) rarely collected although it was the second Herts record previously from Balls wood, Hertford. (fig 4)

Fig 4 ‘Saccosoma farinacea’

Two interesting discomycetes were found on a rare wet morning in June, both growing together on an old Nettle stem. Firstly the noticeable orange pustules of Laetinaevia carneoflava which looks very much like Callorina neglecta, this is usually found in January or February. Microscopically the spore sizes overlap, the paraphyses being the key feature, in Laetinaevia carneoflava they are finely filiform and much branched in Callorina neglecta they are swollen at the apices. Growing close to this and much harder to see was the rare Diplonaevia bresadolae. (fig 5).

Fig 5 ‘Diplonaevia bresadolae’

The fruitbodies develop within the host tissue and break through producing cream/pinkish discs with white ragged margins. Still with cup fungi an interesting Hymenoscyphus like species grew on an old Rubus stem. The almost stalkless clusters of white fruitbodies, turned reddish/brown on bruising. I remember collecting something that looked the same and sending it to Kew in 2008 but then there was no name for it, but they did have several similar collections. I sent it to Peter Thompson who told me it was now called Pseudohelotium haematoideum. (fig 6)

Fig 6 ‘Pseudohelotium haematoideum’

Another find also identified by Peter was Calospora arausinca on a dead attached Oak twig. It is a black pyrenomycete that has perithecia in small groups on a black stroma. One last interesting fact was two fresh specimens of Battarrea phalloides appearing on the 20th August at Willian, despite the summer record breaking temperatures of 40c.