Killerton, ColumnJohn & the Culm

This is about the archaeology involved with tree planting and waterways. The National Trust has a Green Recovery Programme for improving nature…. but this while enhancing and valuing the historic landscape..

The River Culm at Columbjohn

A snowy Sunday afternoon in Warminster… but today let us imagine ourselves out west and at the front door of Killerton House in Devon.

The Acland family gave the mansion and the 2600 hectare Killerton Estate to the National Trust in 1944 …but their first house was down by the River Culm. A Domesday manor which they acquired in the late 16th century. Killerton Estate could have been the Columbjohn Estate if the Aclands hadn’t decided to move.

Killerton House

Columbjohn House was a Tudor rebuild of the medieval manor.. but after its capture by Parliament, during the Civil War, the family decided to shift to a newer acquisition 2km to the east at Killerton. They took up residence in the late 17th century but still valued their roots at Columbjohn.

The 1756 estate map shows an avenue of trees leading straight across the farmland to the river. Halfway along, there is a domed hill with the ruined folly on top (we excavated there in 2017 https://archaeologynationaltrustsw.wordpress.com/2017/07/30/killerton-folly-day-2/ ).

The avenue, with its track back to Columbjohn is long gone… so, from Killerton we must drive back to the park gates passing below Dolbury Hill’s Iron Age hillfort. Once at the gates, we turn right and along a winding road to eventually reach Columbjohn and the river.

The old gateway c.1600 that once gave access to the now demolished Columbjohn manor house

There is an older stone arched gateway here, dated to about 1600, and this once gave access to the drive to the house… but now there is just an area of grass where it once stood. The 1888 Ordnance Survey map marks a cross on the site and if you fade this out as a GIS layer on LiDAR, the cross sits neatly in a rectangular hollow… on the lip of a straight-edged terrace above the River Culm. Once there would have been a good vista from the lost mansion across the floodplain and the meandering river.

The OS 1888 map showing the site of Columbjohn mansion. The cross on this maps fits in the centre of a house platform shown as a neat rectangular earthwork on LiDAR images.

So, the old mansion was demolished after the move to Killerton but Columbjohn chapel is still there. It lies amongst some trees and the Acland family still valued this place as a burial ground. In the graveyard is the imposing tomb of Thomas Dyke Acland who took the name of his wife Elizabeth Dyke, heir to the 5000 hectare Holnicote Estate in Exmoor. They married in 1753 uniting the two great estates.

The grave of Sir Thomas Dyke Acland beside the chapel at Columbjohn

I brought you to the river to talk about river archaeology. From the site of Columbjohn, the Culm takes its sinuous course north along the floodplain, to the west of Dolbury Hill and Killerton Park as far as Silverton and the Killerton Estate boundary.

Columbjohn Chapel

This river meadow land has been chosen as an area for habitat improvement.

Paul, the project manager, phoned last week and talked about the ambition to plant trees, enhance meadow pasture and create wetland areas. This work had the potential to affect archaeological sites along the Culm both known and unknown and we agreed to first have a focused historic landscape survey of the project area which could inform the ‘Green Recovery’ scheme. Then, once proposals had been formulated, a heritage impact assessment to highlight what additional archaeological recording work and evaluation was needed before the digging and planting work began.

We needed someone who had a particular knowledge of waterways and river archaeology and we were in luck. The Culm had been chosen as a pilot study area by Historic England and had employed Antony to do the work, a specialist on the archaeology of waterways, meadows and wetlands.

Before phoning him, I did some homework on what we already knew about the area. I went through aerial photographs, documentary maps and LiDAR. Amazing what can be done digitally by overlying map and photo layers.

The Culm is a restless river, a classic geography lesson in oxbow lakes and moving meanders. Past generations had tried to tame the river but it was hard to pin down.

The 1888 OS map showing Columbjohns Corn Mill just before it burned down. Leat, sluice gates and footbridge shown. Perhaps there had been a mill on the site since the medieval period. The water structures and channels needed to be constantly checked and repaired to maintain the flow across the water wheels to grind the grain.

Just north of the Columbjohn Chapel is the site of Columbjohn Mill. It is clear on on the 1888 Ordnance Survey Map, but burnt down in April that year and was never rebuilt. There had been a mill at Columbjohn since at least 1086. The Area Ranger Fi and her team of archaeology volunteers have cleared the scrub from the site and the mill footings and leat channels have been revealed.

After the 1888 fire, the 1904 OS map shows that the mill has gone.. though the water channels remain

It had been difficult to keep the mill fed with water along the leat from the Culm. The maps show sluice gates and a weir which impeded the water flow and raised the water level so that it could be sent down towards the mill. The river wanted to move west and its course today is different from 1888. There were mills all along the river and regular disputes between neighbours…when leat and sluice work of one miller impeded the water flow to the next mill.

High rainfall would provide too much water so systems were needed to divert the overflow. In dry weather, every drop of water was needed.

The weir and boat house at the 18th century Cubbyclose Cottages. The weir raised the river water to send it down the mill leat towards Columbjohn Mill.

Beside the weir there is a cottage called ‘Cubbyclose’ and there was once a boat house there. Antony wondered whether the Aclands brought guests here to enjoy fishing and wildfowling.

Across the flood plain are linear divisions, clear on the LiDAR, earthworks across the old, grassed over meanders of the river. He talked of water meadows created for a flow of water across the pasture to raise temperature for an early growth of meadow grass to fatten livestock in the spring. A valuable Tudor farming innovation though Killerton’s water meadows are undated.

Antony talked of fish ponds and osier beds for coppicing willow for withies. From these baskets and fish traps could be woven.

Beneath all this historical stuff lies the potential of water-logged preserved wood from hidden lost mills and jetties and trackways across the marshes…who knows…. but the people of Dolbury hillfort and their predecessors would surely have used the watery resources of the Culm.

We’ll see what we find.