Very helpful post mazex, thanks.
According to the University of Reading website:
"Since 1945 the UK has lost:
95% of its wildflower rich meadows
30 -50% of its ancient lowland woods
50% of its heathland
50% of its lowland fens, valley and basin mires
40% of its hedgerows"
Of the hedgerow loss, some part would be down to urban sprawl, some due to grubbing up or neglect of rural hedgerows. I have not yet found a way to quantify this, but have some ideas if I can find the numbers for land area usages.
So if we had 100 miles of hedges in 1945, now we have 60. So if we took a square grid representing hedges now, and imposed another set of horizontal lines over it we would double the number of "fields" with a 50% increase in hedge length giving us 90 miles of hedge. We can assign the remainder to urban sprawl as a first estimate.
So I was also a bit surprised that the 1945 and now photos seemed to show almost identical field boundries and numbers. This could just be regional variation, but...
then I remembered that many hedges are not grubbed up, they are simply neglected. When you neglect a hedge it slowly morphs into a line of trees, the most vigorous survivors shading out the laggards, with bank or ditch (if present) eroding away. The line of trees may eventually be felled (or, if elm, destroyed by the evil Dutch).
So it may be that some of the field boundries in the photos that were hedges in 1945 are now lines of trees or even just tractor paths. Now we need a photograph interpreter sub-forum.
So it looks as though COD gets the number of fields about right but is ailing in the hedgerow/tree management department.
(What a pity they did not use satellite mapping as a first estimate, then we could all be having fun finding our houses and farms....)
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