Category: Lichen

This wooded gorge has a wonderful diversity of lichen. The site is noted for species characteristic of old woodland such as  Thelotrema lepadinum and Arthonia spp. These are indicative that the Dene is a remnant of more extensive woodlands that once grew in this area. The lichen in the picture below with pimple like openings is Thelotrema lepadinum, the dark linear marks are the lirellae of Graphis scripta or possibly elegans.

The prominent black starry marks below belong to probably Arthonia radiata.

Ramalina farinacea is common in woodlands; it is the pale green foliose lichen growing beside the moss (Orthotrichum sp), on this twig.

Although we were looking for and failed to find Ramalina fraxinea, this striking R fastigiata made up for any disappointment.

The yellow lichen colonizing the acid rocks of the gorge by the waterfall was difficult to identify from a photograph or by sight, but is probably a species of Chrysothrix.

Evernia prunastri was prevalent, as was to a lesser extent Plasmatia glauca, Usnea subfloridana and Hypogymnia sp. The picture below shows a Hawthorn tree festooned with foliose lichen of various kinds.

Opened in 1833, designed by Newcastle architect John Dobson, the church has many historical and architectural features of interest. Its graveyard contains many significant memorials. These are made of sandstone, limestone and marble which play host to numerous lichens. Lichens are perilous to identify by sight and poorly defined digital photographs.

Lichens are not a single species but organisms consisting of alliances of various fungi and algae. Lecidea grisella below is a crustose lichen, lecidea means ‘shaped like a little disc’ referring to their black fruiting bodies.

Lecidella scabra below forms a crust of green and grey. Scabra means flaky or scabby. Lecidella means ‘even smaller little discs’.

I think the lichen below is Lecidella stigmatea another crustose lichen of variable colour.

Lichen often forms mosaics with an assortment of colour and variety like an abstract painting.

This attractive bluish one is probably Verrucaria nigrescens or ‘warty black’ lichen. as can be seen lichens often grow on top of each other since they compete to reach the light or gain a foothold.

The lichen below could be Rhizocarpon reductum. Rhizocarpon means fruits with roots. Reductum means reduced, so reduced that they are not visible at all.

The glowing green is from Psilolechia lucida. It means bright naked plates. It is commonly found on sandstone in churchyards.

I am unable to identify this crustose lichen below; it could be Micarea lignaria growing over another lichen?

Lichens also grow on trees and twigs. I noticed a few on  recently sawn logs since most grow up on unreachable branches. This light green foliose or leafy lichen on the trunk is Xanthoria parietina. Xanthoria means golden yellow so the lichen is sometimes called the ‘sunburst lichen’.

The one below is Arthonia radiata, a common trunk lichen. Arthonia is ‘to sprinkle’ in Latin, referring to the appearance of the black marks or apothecia.

Another bark lichen Arthonia punctiformis below. The fruiting bodies emerge from the little holes.

The brilliant jade green below is from Lecanora polytropa. Lecanora means pretty litttle cups and polytropa means ‘many troops’.

Lichen also forms carpets on wood. The green lichens, Physcia adcendens and P Tenella are often found together. The name means ‘sausage like’ from their inflated tips of their edges. Notice the Lecanora growing nearby, probably L chlarotera.