A team of archaeologists at OA North has demonstrated that it is possible to undertake exceptionally beneficial archaeological research within a development context. The CNDR road scheme was commissioned by Cumbria County Council and covers an area of approximately 30 ha. The project has made major contributions to the understanding of the landscape immediately surrounding Carlisle, and the results are highly significant regionally and nationally. Specialists, from a wide range of disciplines, and representatives from CCCHES and EH, regularly visited the site and the resulting recommendations were built into the project methodology as was applicable. One such specialism, the identification and quantification of pollen grains, has been used to aid interpretation of cultural and vegetational palaeoenvironmental changes from palaeochannel sediment sequences at the nationally important site of Stainton West, from which stone hand-axes and wooden tridents were recovered. The palynological research has been used to provide an understanding of the past ecology and environment at the site and to interpret human practice and past activity.
The channel environment
Pollen data provide clear evidence for changing vegetation, derived from both local and regional sources, during the time period from the late Mesolithic to the Bronze Age. The pollen data suggest that in the late Mesolithic, during which time organic and subsequent alluvial sediments were being deposited, a dense covering of hazel thicket dominated the floodplain and mixed deciduous woodland occupied the drier terraces. By the early Neolithic, the arboreal aspect was changing, with primarily elm and subsequently oak, being removed (possibly selectively), from the deciduous woodland cover. Following the elm decline (a decrease in elm pollen frequencies which took place around 4000 cal. BC throughout Britain and northwest Europe), a major switch in vegetation type is seen on the floodplain, with abundant alder replacing the original dominance of hazel. By the late Neolithic, alder woods were well established on the floodplain although hazel continued also to be an important component of drier areas on or adjacent to the floodplain. In the late Neolithic, herb pollen, for example, grasses, became increasingly important in the pollen profiles and as the sequence moves up into the Bronze Age, pollen of grasses and sedges dominate the vegetation. During the period from the Late Mesolithic to the Bronze Age, evidence from pollen data may be interpreted to show that the channel environment and surroundings changed completely from wooded habitats adjacent to a water body, to an open grassy damp environment, practically devoid of trees.
The human impact
Separating out anthropogenic influence on the environment, based on pollen data, from changes caused by agencies such as animals, disease and climate, is very difficult as any of these agents can result in similar changes in the pollen profiles. However, the balance of evidence suggests probable human impact as a primary cause of vegetation disturbance. During the late Mesolithic, this evidence is largely based on indicators of fire in the local/regional environment, interpreted in pollen assemblages from counts for microcharcoal particles. Other proxy data, such as occurrences of certain types of fungal spores and pollen of various herb types, are suggestive of possible human impact, for example in the creation or maintenance of pathways through which animals or people could move to access water from the river. In particular, when these proxies are correlated with other lines of evidence, for example, evidence for worked / coppiced wood, the case for human manipulation of woodland resources is strengthened. At the very least, people and animals would have disturbed the woodland habitat allowing the development of ruderal and possibly early seral stage taxa. A major impact on the environment, possibly due to human activity but which would almost certainly have been taken advantage of by humans in the area, is the decline in elm trees during early Neolithic times. The subsequent expansion of open areas within the woodland and occurrences of pollen types referable to cereal-types and associated weeds supports the development of low scale early agriculture. The location of wooden artefacts (for example, tridents) during this time testifies to the presence of people in the local environment. The effects of humans on the landscape persists through to the Bronze Age in the pollen profiles, with further clearance of woodland and expansion of grasses.
Image: fungal spores and pollen grains