Late afternoon strolling down after a couple of youths and their dogs – two lurchers prancing about off lead, another wears a muzzle and is on a long leash made up of 2 leads knotted together, taking up the rear is a sliver/grey short haired pup called Hugo, wearing a brace that matches the red half of the long leash. Hugo isn’t able to hop over the barrier with the others so he takes the style before me. I’m hoping they are not out for a dusky hunting session on the ponds.
I stop at the trunk of a tree admiring the lichens rich patterning I frame it in my camera and like the way it looks, the spine of a book, or the gutter with a page open on either side. The trees with mosses and lichens are beech, field maple, oak and the lovely rich brown bark of the swamp cypruss.
From Jenny Seawright’s web resource at http://www.irishlichens.ie/index.html
Lichens are dual organisms; a fungus and one or more algae in a stable, mutually beneficial (symbiotic) partnership. The fungus provides structural form and protects the algae from extremes of light and temperature. Algae are capable of photosynthesis and some of the sugars produced provide the fungus with energy for growth and reproduction. Some lichens can live for many hundreds of years and being sensitive to pollution levels they are important enviromental indicators.
I am learning about how lichens on trees might favour an Acid bark Bark of trees with relatively low PH e.g Oak, Beech, Birch or a Basic bark Bark of trees with relatively high PH e.g Sycamore, Maple, Elm
Words for lichens’ living arrangements: Symbiont One of two partners living together, Thallus Vegetative body of lichen, contains both fungal and algal cells and Substrate Material or medium on or within which an organism grows and usually derives nutrients from and terms for lichen mixes:
Words for describing the form of lichens: Maculate. Blotched, patchy or spotted and Marginate. With clearly defined edge and Reticulate. Netted, with net-like pattern and Umbilicate. Attached only at a central point
I see the lichen on the fallen willow and now I know its name Cetrelia olivetorum:
“Large greyish thallus, lobes with small, scattered, punctiform pseudocyphellae on the upper surface and marginal soralia. Underside of lobes black with simple rhizines in centre, becoming smooth and whitish-brown near tips. Apothecia absent.
Three chemotypes; K-, C-, P- or K+ red, KC- or KC+ pink or red.
Infrequent on mossy, acid-barked trees like Hazel and Salix in damp, well-lit woodland. Scattered, local distribution in Ireland.” says Jenny Seawright
Thallus. Vegetative body of lichen, contains both fungal and algal cells.
Punctiform. Small, sharply delimited
Pseodocyphella(ae). Pale line, dot or patch where cortex is thin or absent
Soralium(ia). Structure or region of thallus producing soredia
Soredium(ia). Small powdery propagule containing algal cells and fungal hyphae
Rhizine(ae). Root-like attachment organ from lower cortex
Apothecium(ia). Disc-shaped or elongated fruiting body that contains the ascus(i)
Ascus (pl. asci) – sac-like cell(s) found within an ascoma and formed during the process of sexual reproduction, containing ascospores. asexual propagules – these contain both the fungal and photosynthetic partners needed for the lichen to disperse without the formation of sexual spores, e.g. soredia and isidia.
Soredium(ia). Small powdery propagule containing algal cells and fungal hyphae
Hypha(ae). Fungal filament
Isidium(ia). Tiny detachable outgrowths containing both fungal and algal cells for vegetative dispersal.
Chemotypes. Members of a species differing in their chemical constituents.
The heron is in the bayou, alone tonight a walker stops to capture him
I seem to arrive to the park these days the same time as the dirt bike riders, dusk is their time too, carving arcs in the mud
I arrive at the corner where A and I saw the glittering lights yesterday and try to remember how it all appeared. I head to the road and see the now historic sign at the entrance to the park, in dramatic light, 15 years on – still regenerating.
