Killerton, Culm and Pollen

I have 5 minutes.

Tim is giving the introduction to the Killerton Green Recovery Project. He is talking about wetland creation and areas of habitat formation and woodland planting.

This is our contribution to ‘Winterval’, a National Trust South West virtual conference. Tim is in the Rangers Base at Killerton, Devon and I’m in the, today empty, Tisbury hub in Wiltshire.

The conference is all about nature enhancement. Bringing back the wildlife by extensive habitat enhancement on the lowland estates.

I have 5 minutes to speak up for historic environment. It’s been a quiet day.

I want to talk about the multi-faceted jewel of the English Landscape, that National Trust cares for the design within its topography, its poetry, its artistry, its ecological wonders and of course that multi-millennial layering of human endeavour.

People in need.. homing in on the advantages of geology and terrain…

That National Trust has huge potential for positive land management… works best when it understands and balances the significances of each place.

Too much for 5 minutes?… Aren’t people the problem that have caused the decline in nature? Are Historic Environment specialists…are Archaeologists out of step? Don’t we understand the urgency.. the global war against Climate Change?

All is possible with balanced and inclusive planning.

I’m on…

‘Can you hear me?’….. a pause.

‘Yes, you’re coming through loud and clear’..

I imagine the South Western scattered staff listening… inhabiting homes and offices and Land Rovers from Hidcote to Cape Cornwall.

Map of Killerton Park and Dolbury Hill. The Culm floodplain runs top right to bottom left. Blue dots archaeological sites, red lines scheduled monuments. Stippled area bottom right is Killerton registered park.

‘This is a map of Killerton Park and the River Culm floodplain from Ellerhayes to Collumpton. It is LiDAR faded over the Ordnance Survey. A terrain model with the names of places breathing through it. The stippled zone is the registered park and the red lines are the scheduled monuments. The blue dots are the known archaeological sites.’

I think I’ve sent them all to sleep.

‘Note the lack of blue dots in our Culm floodplain Green Recovery project area. Absence of evidence is not evidence of absence…to coin a phrase.’

‘We should expect particularly fine preservation in the river deposits. That red circle at the top of the hill overlooking the river is Dolbury Iron Age hillfort and flint from here shows that Bronze Age, Neolithic and Mesolithic peoples occupied and reoccupied this vantage point over thousands of years.’

Anthony’s themed Culm floodplain analysis (left) . Each area accompanied by detailed assessments (right)

‘Timber and organic remains survive in waterlogged deposits. There may be woven timber trackways, fish-traps, jetties, sluice gates, leats and waterwheels… who knows? There is high potential for preserved environmental remains. Pollen and plant fragments which will give the biological biography of the riverine environment’

We need to be careful where we plant our trees and excavate out scrapes.

Wetland archaeologist Anthony completed Killerton’s Culm floodplain study and heritage impact assessment. Petra checked out the Culm’s soil profiles.

She spent the summer test pitting, sampling and augering along the river and her report has just arrived.

I show them pictures of pollen. How tiny, beautiful and ancient they are.. sitting quietly preserved in the watery silts for such a very long time.

‘And here at last is the whipworm egg’.

A picture of it had been highlighted in the preamble for day two of Winterval.

‘Lost from the gut of some medieval farmer …buried in a deposit containing large numbers of cereal pollen. ‘

Petra’s report notes that the percentage of cereal grain here is remarkable. Found in the upper deposits near Columbjohn. Perhaps intense local cereal production but also the proximity of grist mills using the river’s power to make flour from ground wheat.

The river has snaked and meandered, backwards and forwards, cutting and recutting its path. The LiDAR shows the palaeochannels. Different survivals in different places will reveal different time zones of the story. The types of pollen indicate huge changes in the environment through time.

Petra gathers the percentages of pollen types in coloured blocks on her bar charts. The woodland pollen is light green, the grassland herbs are blue, the ferns dark green and the cereal yellow.

At Cubby Close Cottage, near the middle of the project area, the organic remains are very good. Certainly earlier than the Columbjohn sequence. At 90cm down the augured column, the deposit contains 8% cereal pollens and 26% woodland. At 120cm, the cereal is down to 4% and the woodland is up to 48% but at 150cm 90% of the pollen is from trees, nearly all alder and the rest herb and fern pollen. No cereals are detected.

Petra would need funding for C14 dating to pin down dates more precisely but dense alder woodland is typical of Neolithic/Bronze Age pre-farming river valleys. At 150cm The Cubby Close Cottage deposit demonstrated a pre-farmed landscape. Higher up the column, the impact of settlers becomes clear. People felling the woodland and turning the land into fields to graze stock and plant the first crops.

The deep alluvial deposits across the Culm floodplain are a direct result of this Bronze Age deforestation 4000 years ago. The alluvium happened as the farmer settlers converted the valley to farmland. They created an open ploughed landscape, made it vulnerable to soil erosion after heavy rain, sending the ploughsoil downslope into the river.

Petra found a similar pollen landscape pattern on the Aller within the Holnicote Estate on Exmoor. Similar National Trust nature recovery schemes will create opportunities to compare pollen profiles along the Stour at Kingston Lacy in Dorset and the Windrush at Sherborne, Gloucestershire. Four counties, four geologies…how would they compare?

Archaeology turns out to be quite relevant to the historic/natural environment interface.

All this archaeological preparation on the Culm meant that we dodged the significant deposits. The archaeological watching brief during the excavation of the scrapes for wildlife revealed one Victorian bottle marked ‘Ascetic Elixir’ and two scattered machine cut timber planks.

Back to Winterval…. 2 minutes left and two more slides.

‘Now, about tree planting and the need to pre-plan for geophysical survey…

1889 OS map Higher Burrowton, Killerton Estate where new woodlands have been created and geophysical survey has been carried out by Marin and Anne of Tigergeo.

after all, absence of archaeological evidence …is not evidence of archaeological absence.

Today we have naming of parts. Yesterday,
We had daily cleaning. And tomorrow morning,
We shall have what to do after firing. But to-day,
Today we have naming of parts. Japonica
Glistens like coral in all of the neighbouring gardens,
And today we have naming of parts.

Henry Reed.

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