Restoration of lapsed beech pollards: Evaluation of techniques and guidance for future work

We examined the impact of two pollard restoration techniques on 38 ancient, lapsed beech pollards in the Basque Country (northern Spain) in four locations from 2007 to 2009. In 2007, prior to the trials, the trees were generally in good condition. Trials involved recutting the branches of trees with axes and/or chainsaws, and compared traditional Basque-style cuts, immediately above the bolling (main stem) close to the site of previous pollarding cuts, with gradual restoration techniques involving significantly smaller reductions of the canopy branches.Although one tree died following cutting, the responses of 36 pollards in 2009 (the third full season of regrowth), were generally good across the sites. Responses measured included the production of new shoots from dormant buds below the cuts and increases in the annual extension growth of retained branches. Stub length of cut branches was important with stubs longer than 500 mm producing significantly more new shoots from dormant buds. This finding supports results from recutting ancient beech pollards in England. The Basque-style cuts promoted more and longer epicormic growth. In addition, axe cuts encouraged more new shoots on cut branches, although the sample size and the possible confounding factor of stub length requires that this result be investigated further.