Gwinear is a treasure trove!
This is my first foray into trying to identify lichens.
In the photo above is a smooth green lichen covering the stonework around the Indian-head Mason's Mark on the 15th century tower of Gwinear Parish Church.
I look at the orange crustose lichens below every day. This slate upstairs-window ledge is part of a sixteen year old extension to our stone cottage, just a mile from Churchtown.
The lichen below is Xanthoria parietina, the large patch is six cm. long and 4cm. wide. My vocabulary is increasing every minute, thanks to a text book by Frank Dobson.
The Body or Thallus of this lichen, as you can see, is not differentiated into stem, leaves and roots. It does not grow from one point, but appears to gradually cover and hold to a hard surface. Parietin is a bright orange pigment which protects the algal cells from too much sunlight. Lichens require sunshine, rain ( plenty of both in Cornwall), and unpolluted air. The lobes at the outer edge on the Xanthoria are foliate (leaf-like) and some are rising just a little from the slate at the edge of the Thallus. The little raised cup shaped discs with lobed edges in the central area of the Thallus are the apothecia, or fruiting bodies.
Lichens are complex plant- like organisms. All are made up of algae or cyanobacteria living among filaments of a fungus in a symbiotic relationship. This association of algae and fungi is usually beneficial to both.
RAMALINA siliquosa (above and below top right,) from the South wall of the church. The Thallus is tufted, greenish -grey and stringy looking. It has just one holdfast. The minute white seed pods, or soralia, are distributed along the thin outer stringy margins below on middle right.
Ramalina subfarinacea, or sea ivory, covers the cross below completely.
The Ramalina branches are small and much divided. A diffuse, spreading holdfast enables it to form a dense sward. This burial area (no.3), is within sight (just) of the sea near Hayle.
In 1990 there was a two day study, by members of Cornwall Wildlife Trust, of the wildlife across three of the four burial areas at Gwinear. I noticed that there were ten lichens listed. For this beginner's project I looked up each one. I have not yet found Rhizocarpon geographicum, the map lichen, but have seen an utterly gorgeous example from Norway, on line.
If you can help me by correcting any mis-identifications or errors, I would welcome that. Please use the 'Contact us' section in 'Around our villages today' within gwinearparishchurch.org.uk. Press 'please contact Beth!'
I think that interest in lichens will increase because the smart phone cameras give such detailed images. 'Caring for God' Acre', available within the links section of the website, provides a superb lichens investigation page for beginners young and old. It encourages describing and distinguishing lichens without using their names 👍.
Beth Saundry- Gwinear's canny wee Lay Weeder
6th January 2016
Credits:
Beth Saundry