Data collection
At each of the 10 study sites, 12 D. antarctica trunks
were examined for epiphytes. Selection of trunks was
random except that only live tree-ferns greater than
two metres in height were chosen. Shorter ferns often
have a ‘skirt’ of persistent dead fronds around the
trunk, creating a dark and dry environment, which
is unsuitable for epiphytes (Page & Brownsey 1986;
N. R. Roberts pers. obs. 2002). Ferns leaning on
other substrates were also avoided. At sites where
C. cunninghamii was present, up to 12 trunks of this
species (or as many as available and suitable) were also
examined. For each trunk, all fern and bryophyte epiphytes
that could be reached (i.e. below about 3 m),
were recorded, plus any identifiable species that were
beyond reach. Epiphyte loads above 3 m were usually
very low.