Neolithic and Bronze Age Landscapes of North Mayo: Report 2011

at Glenulra scatter. Alder was identified only at Belderg Beg, where it was important and at
Rathlackan where it was less so (22% and 1% respectively). Both these trees indicate the
presence of streams, mire or carr woodland. Ireland’s native tree is the black or grey alder
(Alnus glutinosa). It can often be seen growing on mire sufaces, alongside rivers, lakes, in
marshes or in fens. A consistent and abundant supply of moisture is essential for its
germination and early growth. The tree can grow up to 25m, and can attain a maximum girth
of up to 1m. The tree can reach ages of between eighty and one hundred years (Stuijts 2005,
139). Willows are not naturally a woodland species, although shrubby growth may occur
under light woodland cover. All willows favour wet conditions, and it may be a pioneer
species on wet soils (Orme and Coles 1985, 10).
A hint of scrub is noted from all of the sites with the exception of Glenulra (E24) with the
identification of pomaceous fruitwood (Maloideae). The Maloideae group, a sub family of
the Rosaceae includes crab apple, wild pear, rowan/whitebeam and hawthorn. It is
extremely difficult to separate these through wood anatomy. Crab apple (Malus sylvestris)
tends to be found on woodland edges (Hickie 2002, 55). Wild pear (Pyrus pyraster) is mostly
found as an isolated tree (Stuijts 2005). Rowan (Sorbus aucuparia) is a tough colonizer which
can tolerate peaty soils and exposed conditions. It needs plenty of light to thrive (Hickie
2002, 65). Whitebeam (Sorbus aria) grows up to 20m high and has a preference for
limestone soils (Orme and Coles 1985, 11). Hawthorn (Crataegus monogyna) can thrive in all
but the most acid of soils (Gale and Cutler 2000). As wild pear is not a native Irish species, it
is likely that the charcoal represents other types encompassed in the Maloideae group. A
possible endocarp (core) fragment of (crab-apple) was identified from C. 93 in Rathlackan
(Mc Clatchie 2010, 2), which may indicate that the Maloideae charcoal identified from that
site represents apple wood.
Pine was noted on Glenulra, Belderg Beg and Rathlackan. It prefers light, sandy soils, and
does not like sea winds or high rainfall. However, it can tolerate these conditions and
therefore grow on marginal land (Hickie 2002, 66). A comprehensive programme of
radiocarbon dating has been undertaken on bog pines from the Céide fields (Caulfield 1998).
A pine horizon developed in the area over 100 years, centered on 4150 BP (4700 cal. B.P.)
(Molloy and O’Connell 1995). In general, pine grew on the bog basin before the Neolithic
period but appears to have either no longer grown by the Neolithic period or to have been
present in very low amounts (O’Connell and Molloy 2001, 104-105). This is probably why
only three fragments were identified from the whole charcoal assemblage, still it does
demonstrate the trees presence (albeit sparse) into the Bronze Age.
Some other canopy trees identified from the charcoal assemblage include holly, yew and
elm. Holly was identified at the Ceide Visitor Centre, Belderg Beg and Rathlackan. Both yew
and elm were identified on one site only, Glenulra and Rathlackan respectively. Holly is a
hardy tree and can be found on higher, exposed ground or growing underneath taller forest
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