Recently I came across a couple of examples of regrowth that are worth sharing. These were in a short length of wide-spaced Hawthorne hedge, laid approximately four years ago, which has the look of a practice piece, or a job that was not completed. Whilst the stems had been pleached there was no evidence of stakes or binders and there was no 'build' to speak of. So, not much of a hedge but it does illustrate nicely a couple of issues around regrowth.
The regrowth has not been trimmed and has reached between six and eight feet in height. There is little competitive vegetation at the base of the hedge, aside from some low-level bramble, and the new stems are thin, straight and only lightly branched.
The first photo shows strong regrowth from the stool, in fact there are a surprising number of new stems. There are two old pleachers, so it was multi-stemmed when laid, and may well have been previously coppiced.
I believe that this second photo shows a pleacher that has not been thinned down sufficiently when laid and therefore a greater proportion of the sap is feeding the pleacher rather than the stool. This has caused vigorous growth in the pleacher with many new sturdy upright stems. In time the pleacher will rise further off the ground and if it were some time before it was laid again it would present a problem for the hedgelayer trying to make a stock-proof hedge.
We have all come across these large old pleachers, still alive and with multiple upright stems, and are none too happy if we get a difficult one in a competition cant. I think this example nicely illustrates how these occur and why we should endeavour to get the 'hinge' to the optimum thickness to keep the pleached stem alive, whilst promoting strong regrowth from the stool.