VSF 2010 Report - Nabo

Discussion
Origin of Charcoal
As mentioned above, identification of charcoal from the samples taken from this column
revealed that all of the 950 fragments analysed were of the genus Betula (birch/björk). This
is somewhat unsurprising as Iceland has a very limited number of tree species, as is
illustrated in Table 2.
Table 2. Tree species native to Iceland, with English and Icelandic names and habitat information.
After Kristinsson 1998.
Species Name English Icelandic Habitat
Betula nana Dwarf Birch Fjalldrapi Dwarf-shrub heaths and mires. Common.
Betula pubescens Downy Birch Birki Moderately dry soil from lowlands to 450m
a.s.l. Scrubland along coasts with taller
brushwood and trees inland. Common.
Populus tremula Aspen Blæösp Heaths and woodlands. Very rare, found only in
parts of the Eastfjords and in Fnjóskadalur in
the north.
Salix callicarpea Bluish Willow Grávíðir Heathland and slopes, especially in the
mountains. Common.
Salix herbacea Dwarf Willow Grasvíðir Heathland, snowbeds and depressions in
mountains. Common.
Salix lanata Woolly Willow Loðvíðir Heathland, dry slopes and sandy banks.
Common.
Salix phylicifolia Tea-leaved Willow Gulvíðir Meadows, river banks, slopes and heathlands
with moist soil. Forms undergrowth in damp
birch woods. Common.
Sorbus aucuparia Rowan Reyniviður Birch woodland and gorges. Does not form
woods, but is found singly in birch woodlands.
Amongst these species, Betula pubescens (downy birch/birki) is the only tree which
forms woodlands. It is also one of only two tree species native to Iceland which grows to a
full tree form, rather than a shrub or creeping form. The other of these species is Sorbus
aucuparia (rowan/reyniviður), however this species only grows singly within birch
woodland, rather than forming woodlands on its own. It is assumed, then, that the charcoal
found at Vatnsfjörður is of Betula pubescens wood rather than Betula nana (dwarf
birch/fjalldrapi), however as the two species are indistinguishable by wood anatomy alone
(Schweingruber 1982; Hather 2000) it is only possible to be completely certain of an
identification to genus level. It is, however, somewhat unusual that 100% of the samples
analysed were identified as Betula. Previous investigations into charcoal from Vatnsfjörður
have shown that willow charcoal was also present, albeit in very small amounts (Mooney
2009), and investigations into fuel use at other Icelandic sites have also identified willow
as well as birch (Zutter 1992; Simpson et al 2003; Vésteinnsson & Simpson 2004;
Sveinbjarnardóttir et al 2007). Rowan has not been identified in wood charcoal from
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