ASCOMYCOTA | LECANOROMYCETES > LECANORALES > Cladoniaceae

Common name:            Organ-pipe Lichen (seldom used)

Synonym:                    Cladonia crispata var.cetrariformis

Habitat:                          Heaths, moors, peat bogs, acid woodland

Substrata:                      Acid soil primarily, but also on decaying tree trunks

Growth forms:              Terricolous, lignicolous        

Basal thallus:                  Squamulose

Secondary thallus:        Podetia

Apothecia:                    Lecideine

BLS identity rating:        Graded 2/5 (visual identification possible with care)

The basal thallus comprises small, indented, scattered squamules that have a greyish-green upperside and white underside; persisting at first, but usually disappearing when the podetia mature.

Podetia usually clustered, forming small bushes typically from 20-60mm tall; sometimes unbranched, but usually irregularly branched, particularly towards the apices, mostly with three or four short secondary branches coming from each fork; can be spiny in parts; tips of podetia open, often with 3-6 short spines radiating round the perforation or, in older mature growth, terminating in very narrow, flaring cup-like structures, with short spine-like outgrowths around the margin, usually with one of the spines later proliferating to form an additional extension, which may repeat several times.

Surface corticate, occasionally squamulose towards the base, otherwise smooth and faintly areolate with irregular patches and lines, more evident in paler specimens; colour variable, dependent on conditions (light, shade, damp, dry) and presumably age, being pale grey-greenish to dark brown-grey or brown-green

Apothecia quite often present, although tiny, barely 1mm dia., globose, pale to dark brown, on terminal spines; pycnidia frequent, dark brown, similarly at the apices of the terminal spines.

Cladonia crispata var.cetrariiformis occurs on dry to damp, acid lowland heaths, but more frequently on peat soils in upland areas, also in peat bogs and some acid woodlands where it may be found growing on decaying tree trunks.  

Well-developed specimens can usually be identified by their appearance and colour without problem but younger growth, lacking the terminal perforations surrounded by short spines, can be very similar to Cladonia furcata; but that species has slimmer podetia that are mostly dichotomously branched with pointed apices, and is more likely to occur in less acid habitats.

The more robust form var.crispata is very rare and has only been officially recorded from a few, mainly coastal, locations. Older literature even stated that it didn't occur in Britain, so I guess it's safe to say that it's extremely unlikely to be encountered locally even though the BLS account for the species is accompanied by a couple of photos taken in the New Forest.