PURPLE HELLEBORINE AT WOLVES WOOD, HADLEIGH
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INVESTIGATING THE DISTRIBUTION OF FLOWERING SPIKES OF VIOLET HELLEBORINE EPIPACTIS PURPURATA IN A DECIDUOUS SUFFOLK WOODLAND IN RELATION TO ADJACENT DITCHES AND DIFFERENCES IN HEIGHT ABOVE THE BASE OF THE DITCH, SOIL MOISTURE AND PH DENNIS AND ANNE KELL Introduction This project originated from a chance remark by Dr Stephen Clarkson, East Anglian Branch Secretary of the Wild Flower Society. Whilst looking for Violet Helleborines in Wolves Wood, he commented that they could be found by following the ditches in a particular compartment. Personal observations supported this and the following report forms the basis of an investigation undertaken as part of an OU module during the summer of 2014. Preparatory work was also undertaken in 2013. Epipactis purpurata Violet Helleborine Epipactis purpurata Sm. (Plate 14) is an herbaceous longlived perennial orchid, most commonly found in deciduous woodland dominated by Beech Fagus, Hornbeam Carpinus or Hazel Corylus, tolerating deep shade (Ellenberg classification of 2). (BSBI/BRC 2014) It is a non-bulbous geophyte (perennial plant with buds below ground during dormant periods) with a vertical rhizome from which roots descend vertically to 1∙2 m. It is wasp-pollinated and reproduction is entirely by seed, with no evidence of vegetative spread. It is late-flowering (July – September) with long-lived, older plants producing several flower spikes. (Harrap and Harrap 2009). It is mostly associated with soils such as clay with flints overlying chalk bedrock, but can tolerate acid soils. (Harrap and Harrap 2009). Wolves Wood, Suffolk. The site has been owned and managed by RSPB since 1972. It has been designated as an SSSI (Site of Special Scientific Interest.) and is typical of East Anglian ancient deciduous wet-woodland, lying on boulder clay above chalk, with many ponds and ditches (Plate 15). (Rackham, 1971) It covers 37 ha, is surrounded by arable land and active management of water levels is taking place. (Nowers et al., 2012). The main woodland type is Oak/Ash/Hazel with Aspen managed by coppice rotation. Hornbeam Carpinus betulus is not currently included in the coppice rotation. One compartment covering approximately 1∙5 ha has been uncut for over 100 years (Rackham, 1971) and this supports the colony of E. purpurata. The old coppice stools have developed several trunks, causing some to collapse. The canopy is dense with virtually no understorey or ground cover. E. purpurata faces negligible competition from other herbaceous plants. However, flowering spikes have been grazed during 2014 and there is evidence of both deer and brown hare using the compartment. Preliminary Investigation A survey was conducted in August 2013, identifying positions of plants, marking them (white numbered plastic markers) and measuring shortest distances from the plant to the centre of the nearest ditch. 123 plants were found.
Trans. Suffolk Nat. Soc. 50 (2014)