ASCOMYCOTA | LECANOROMYCETES > LECANORALES > Cladoniaceae

Genus Cladonia, meaning 'branch or twig-like' - specifically relating to these richly branched species

Common name:             Reindeer moss (see Cladonia portentosa)

Synonyms:                     Cladonia arbuscula, ssp.squarrosa

Habitat:                           Heathland, upland moors, dunes

Substrata:                       Acid and/or nutrient-poor soils

Growth forms:               Terricolous              

Basal thallus:                  Crustose, disappearing

Secondary thallus:         Podetia, richly branched

Apothecia:                     -  

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

Primary basal thallus granular, hardly visible, evanescent; secondary thallus shrubby, richly branched, growing in clumps from around 40-100mm tall;

Podetia occasionally branching dichotomous, but predominantly trichotomus or tetrachotomous at the apices, with the terminal branches noticeably recurved and, more or less, orientated in one direction; surface somewhat uneven and roughened    

Colour pale yellow-greenish if moist; but silvery, sometimes almost white, when dry due to the less-broken cortex.

Apothecia rather rare, brown and inconspicuous.

Two forms are recognised, the common subspecies squarrosa as described, and a much rarer form, ssp.arbuscula, that has only been recorded from a couple of locations further north.

There could be confusion with other 'reindeer moss' species, particularly with the similarly coloured, and much more common Cladonia portentosa, or with Cladonia ciliata (var.tenuis). In both cases it is more robust and, in respect of the former, it only appears to be a similar colour in certain conditions as Cladonia portentosa has a more broken cortex that gives it a green tinge when dry. That species also has terminal branches that, at most, are only slightly recurved, but at the apices spread in all directions. Cladonia ciliata is far more delicate, particularly at the tips, and differs in having predominantly dichotomus branching.

Cladonia arbuscula is locally abundant in upland locations, but declining in many lowland areas due to either loss of habitat or vegetation overgrowth. Whilst most Dorset records seem to be from more coastal heathland, the species is still reasonably common on a number of New Forest short-grazed or wet heaths.