Lichen Report for 2018

by Ishpi Blatchley.

My lichen recording effort in 2018 did not include much work in the OFC area so this report will be a bit 'thin'!

Lilly's Wood in Chelsfield has been chosen by Jamie Fletcher as his site for 'patch' recording of birds, and in order to get a better picture of the general natural history and biodiversity of the site, he asked me to do a lichen survey.

Lilly's Wood is a mixed semi-natural ancient woodland of (principally) oak, beech and ash with hazel and holly understory. To the west is an area of mixed woodland planted in 2000. These trees are growing well and now need thinning. Forty-four species of lichens and lichenicolous fungi were recorded over the whole site (See this report: Lichens of Lilly's Wood).

A joint meeting with the Kent Field Club at Scadbury was promoted as a lichen meeting. Fifty lichens were recorded, the hedgerows providing the most diverse (although common) lichen flora with all the usual Physcia species (including P. aipolia) and the Parmelioids Parmelia sulcata, Parmotrema perlatum and Flavoparmelia caperata being present. Ramalina farinacea and an Usnea sp which was too small to identify positively (probably U cornuta) were also found.

On a veteran oak tree (Quercus robur) in an area which was once, probably, wood pasture, the small black pins with brown tops of Chaenotheca trichialis were found In the dry cracks. This is its preferred habitat and I know of only one other record for this species in LBB. Old hazel (Corylus avellana) stools supported two of the script lichens with immersed fruits - Phaeographis dendritica and P. smithii. Buellia badia was found on a gate - this lichen is widespread in the UK but not common in LBB (it occurs on the post and rail fence at Cudham churchyard).

The London Churchyard Ecology Project has reached the end of its first phase and needs extra funding to continue. I have reported on this Project in previous Annual Reports as I have been involved in the lichen recording of the selected churchyards. In brief, 558 churchyards in the Dioceses of London, Chelmsford, Southwark and Rochester and within the Greater London area were subjected to a rigorous unbiased selection technique and 31 churchyards were chosen for detailed Phase 1 habitat and bat surveys; 18 of these were chosen for lichen surveys.

In all, 155 lichen taxa were recorded from the chosen churchyards which included some in inner London (e.g. St Mary Abbott in Kensington) and ones in more rural areas (e.g. Downe). This first phase has been written-up as an article in British Wildlife (2018 vol 30 pp20-27) an uneasy exercise on my part as a paper written by committee is never a comfortable option. However, I felt that the need to push the importance of churchyards for lichens had to over-ride my many misgivings!

Further afield, Keith Palmer and I have now completed our lichen surveys of the (intact) medieval churches of Romney Marsh. The results of the surveys in 2016-2018 have been compared with those conducted in the early 1990s. In almost all cases, numbers of lichens recorded have increased mostly due to better knowledge of saxicolous flora.

Highlights include: Paralecanographa grumulosa (Churchyard Lecanactis) now found in 5 Romney churchyards - previously known from Ivychurch and St Mary in the Marsh, now also found at Brenzett, Dymchurch and Snargate. Llimonaea sorediata, a coastal species mostly found in the West, was recorded from New Romney and Fairford (both times on the church itself). These are the second/third Kent records (VC15). Staurothele hymenogonia has few records post 1999 and it was found at Snargate (new Kent record, both VCs). The very attractive dainty orange lichen, Caloplaca cirrochroa is doing very well on the north wall of Snargate church on lime-washed brick. A species usually associated with hard native limestone, there are only 4 Kent records (all VC15).

Lecanora pruinosa was found to be locally frequent on the tower at Newchurch. This is a Nationally Scarce species thought to be confined to old church walls. It is only the second record for this species in Kent (the other is at Charing) and its stronghold is in Dorset. Pachnolepia pruinata is usually found on trees and is a reasonably common lichen on that substrate. On saxicolous substrates, it forms part of the important 'north wall community' of churches so its presence in this community at Ivychurch and Snargate is of special interest. Diploschistes actinostomus which was found new to the UK at Brookland in the early 2000s is still present on the brick boundary wall of the extension yard and a further colony was found in 2018 on the south wall of the church. The second UK record for this lichen was found at Hever church (VC16) in 2014.

However, it is not all good news. Some lichens have been lost which underlines the importance of repeat surveys. For example, species on lignum, specifically from post and rails, have done badly with Cyphelium inquinans, Imshaugia aleurites, and Lecanora conizaeoides being absent from yards where they occurred previously. In the case of the latter species, its decline with the reduction in acid rain pollution has been well documented and it is now confined to lignum in the south of the UK. The loss of the other 2 species is a result of the replacement of decaying fences.

The most worrying loss of lichen diversity occurred at Snave where the previous total of 80 species is now reduced to about 60. Several important lichens are no longer present and others are under threat due to heavy shading and ivy cover. Our churchyard surveys have contributed to data for the KWT Fifth Continent Project and it is hoped that suitable management of these important churchyards can be instigated.

Compiled March 2019.