REINDEER GRAZING INVESTIGATIONS IN ALASKA 
25 
vidual groups or patches of one or two species (pi. 13, fig. 1). Fre- 
quently some one or two species predominates and numerous other 
species of various kinds are scatteringly intermixed with the base 
plant. Ordinarily, a handful of lichens picked up off the range 
will be found upon analysis to contain six or seven or more dif- 
ferent species closely intermixed. Cladonia is the most abundant 
of the lichens in Alaska, both in number of species and in quantity ; 
Cetraria is second in importance, but of scattering occurrence. 
The predominating species on tundra and lower foothills sites are 
Cladonia sylvatica sylvestris, C. rangifenna, and C . sylvatica, or a 
combination of these. On a rocky subalpine site of favorable ex- 
posure, the predominant plant may often be C. alpestris. On higher 
range, the main plants are often species of C. amaurocraea and C. 
uncialis, and sometimes abundantly mixed with them 0. sylvatica 
sylvestris. On rocky upper slopes and tops of ridges of inferior 
cover, the Cetraria species often predominate. Some species are cos- 
mopolitan in distribution, occurring scatteringly throughout all 
types, as Cetraria cucullata, C. islandica, and Cladonia gracilis elon- 
gata. On rocky upper areas Cetraria nivalis, G. islandica crispa, 
Cladonia gracilis dilatata, and Alectoria nigricans are commonly 
found. Cladonia sylvatica sylvestris stands out generally as the most 
abundant and widespread and therefore most important winter for- 
age plant on the coast range. 
The more important species of lichens occurring on the coast 
ranges may be grouped as follows : 
(1) Most abundant : 
Cladonia sylvatica sylvestris. 
Cladonia rangiferina. 
Cladonia sylvatica. 
Cladonia gracilis elongata. 
Cladonia amaurocraea. 
Cladonia amaurocraea oxyceras. 
(2) Fairly abundant in places 
Cladonia uncialis obtusata. 
Cladonia alpestris. 
Cladonia gracilis ecmocyma. 
Cladonia amaurocraea celotea. 
Stereocaulon alpinum. 
Stereocaulon coralloides. 
(3) Scattering but frequent : 
Cladonia (cup claclonias ) . 
Ochrolechia sp. 
Parmelia sp. 
Cladonia furcata. 
Cladonia delessertii. 
Cladonia crispata. 
Cladonia degenerans. 
(4) Infrequent : 
Cladonia botrytis. 
Cladonia subsquamosa. 
Cladonia cenotea. 
Cladonia cyanipc:. 
Dactylina arctica. 
Duforea ramulosa. 
Cetraria cucullata. 
Cetraria islandica. 
Alectoria nigricans. 
Alectoria ochroleuca. 
Clado ni a u nciali s . 
Cladonia uncialis turgescens. 
Stereocaulon tomen tosum. 
Cetraria chrysa n tha . 
Cetraria nivalis. 
Cetraria islandica crispa. 
Cetraria islandica platyna. 
Sphaeropliorus coralloides. 
Thamnolia vermicular is. 
Nephroma arcticum. 
Lobar ia linita. 
Cladonia gracilis dilatata. 
Cladonia decorticata. 
Cladonia squamosa niuricella. 
Icmadolphila ericetorum. 
Pertusaria bryontlia. 
Pilophorus cereolus robustus. 
Philophorus cereolus- acicularis. 
Cetraria juniperina. 
Cetraria luascens. 
