Coppicing for the shoots used elsewhere simply means the stems are cut off completely of course. Here the idea is that the new growth will become so intertwined as to be impenetrable for most creatures and provide all sorts of habitat for birds and so forth. There is more info..I can't find the site from Britain I was looking for..but this is a good start maybe. Need to protect the thing until it gets established though.
another link which might prove helpful even though it is definitely oriented to EnglandĀ http://www.hedgelink.org.uk/hedgelink/files/NE%20HEDGEROW%20PLANTING.pdf
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