NEOLITHIC AND LATER PREHISTORIC LANDSCAPE OF THE AVON VALLEY 231 
At Durrington (Figure 7) the peat represents 
‘on-site’ organic accumulation on the floodplain 
communities of fen, wet pasture and carr woodland, 
and the inorganic sediments are derived from 
fluvially transported sediments and by colluvial 
processes from the valley sides. Thus, pollen input 
into this location may come from a variety of sources 
but, nevertheless, illustrates the vegetation history of 
the local region. The pollen spectra illustrated in 
Figure 7 provides interpretation of the development 
of the floodplain vegetation and of the dry-land plant 
communities. It will be evident that changes on the 
interfluves may also have had an effect on the 
character of the floodplain. Changes within the 
drainage basin may be responsible for variations in 
sedimentation, organic deposition and erosion of 
sediments which resulted in hiatuses in deposition. 
Durrington: 1 (1.60-1.47m) 
The dominance of Betula (birch) and Pinus (pine) 
in this basal zone and the increasing importance of 
Quercus (oak), Ulmus (elm) and Corylus (hazel) 
suggests a late Devensian to early Holocene age for 
this zone. A radiocarbon date from humic acids 
from a bulk sample (1.60—1.45m) of this basal peat 
of 8640+200 BP (GU-3239), calibrates to 8050- 
7260 cal BC using data from Kromer and Becker 
(1993) with Calib 3, and indicates an early 
Holocene date for peat inception. Fluctuations in 
these taxa appear to follow a pattern typical of 
changes in arboreal and shrub pollen known from 
other sites in southern England. The relatively high 
values of Betula and Pinus, the latter being 
dominant, are typical of the Allerod/Windermere 
interstadial with the lesser values of other arboreal 
taxa (Ulmus, Quercus, and Corylus) considered as 
being transported long distance. 
The vegetation at the very base of this zone 
comprises largely open herbaceous communities 
dominated by Cyperaceae (sedges) and Gramineae 
(grasses) growing in the damper valley bottom. 
This may be attributable to colder conditions in the 
late Devensian (c. 10,800—10,000 BP). Whether this 
was a true river floodplain or a low marshy area 
with perhaps periodic/seasonal outwash, which is 
~ more likely, is speculative. Sharp increases in the 
percentage of Betula followed by Pinus, Corylus and 
Quercus are typical of the early Flandrian 
succession of woody vegetation from 10,000 BP 
brought about by climatic amelioration at the end 
of the last cold stage. Subsequently, Pinus and then 
Quercus and Ulmus with Corylus are represented as 
these taxa migrated into the region. These deposits 
appear to be compacted and thus sampling intervals 
less than 20mm might illustrate this succession 
more clearly. 
Durrington: 2 (1.47-1.17m) 
At 1.47m, there is a marked change in the 
sediments and contained pollen spectra, indicating 
a zone of erosion and marked hiatus embracing mid 
Boreal to Atlantic climatic zones (Godwin’s (1975) 
pollen zones V—VIIa) i.e. Mesolithic. The deposits 
are peaty silts and silts which contain markedly 
fewer tree and shrub pollen. Betula is only 
sporadically present and Pinus although 
continuously represented is regarded as ‘normal’ 
background pollen rain from extra regional sources. 
Tilia (lime) is recorded for the first time. In 
contrast, herb pollen becomes dominant (toc. 250% 
AP or 95% total pollen). This comprises the 
autochthonous, local floodplain community and 
from the drier interfluves. The floodplain was 
dominated by grasses and sedges with other fen 
type plants which include Thalictrum, Caltha type 
(probably including Caltha palustris/ marsh mari- 
gold), Filipendula (meadowsweet),  Valeriana 
officinalis (valerian), and Typha/Sparganium type 
(reedmace and bur-reed). Alnus (alder) is present 
but in view of the very high pollen production of 
this tree (Janssen 1959; Andersen 1973), it is not 
considered to have been important on or near the 
sample site. Non-wetland taxa include a diverse 
range of herbs which are typical of Neolithic or 
post-Neolithic land use subsequent to woodland 
clearance. 
It is clear that there is substantial evidence for 
anthropogenic activity in the local area and 
specifically for arable activity. Pollen of segetals 
(weeds associated with arable habitats) such as 
Fallopia convolvulus’ (black bindweed) and 
Polygonum aviculare (knotted bindweed), Centaurea 
cyanus (blue cornflower) and cereal type pollen are 
typical. Of particular interest are the high 
percentages of Cruciferae (Sinapis type/charlocks) 
which is frequently associated with arable 
agriculture. Here, however, the high percentages 
are likely to be from ‘on site’ growth. A range of 
herbs typical of waste or cleared ground and 
pastoral habitats were also present. Typically these 
include increased occurrences of Chenopodiaceae 
(goosefoots and atriplexes), Papilionaceae (clovers 
etc.), Rumex (docks) Plantago lanceolata (ribwort 
plantain) and Plantago media/major type (hoary 
plantain and greater plantain) and a range of 
Compositae taxa. 
