Every Vice-county is supposed to produce at least a draft Rare Plants Register by 2019. Following an offer of assistance from Chris Metherell, I have been setting to and have produced the taxon list for it.
Selection of many taxa is straightforward:
– Internationally important – endemic to Britain or of restricted distribution internationally, listed in EC Habitats and Species Directive Annex IIb, IVb or Vb; or Appendix I of the Bern Convention or Appendix I or II of CITES
– Nationally important – listed in Schedule 8 of the Wildlife and Countryside Act 1981 or listed as occurring in IUCN categories CR (critically endangered), EN (endangered), VU (vulnerable) and NT (near threatened) in the British Red Data Books for Vascular Plants or nationally rare, occurring in 15 or fewer 10km squares in Britain or nationally scarce, occurring in between 16 and 100 10km squares in Britain.
Those that qualify under local criteria can be trickier: rare (present in 3 sites or fewer in the Vice-county and do not fall into the above categories. In this context a ‘site’ is a discrete area within a moveable kilometre square) or scarce (present in 4 -10 sites in the Vice-county and do not fall into the above categories) or extinct in the Vice-county.
There are numerous issues that make selection difficult – single, old, sometimes anonymous records of a species, changes in taxonomic treatment over the years and in one case a subspecies that is either recorded in error or is too common to be included and in any case is recorded almost entirely only at the 10km square level and so is difficult to check.
I have sent my list, which currently comprises 194 taxa, to Chris who has an automated process for basic formatting and adding national status and distributional details. During the season I will try to check on some taxa in need of attention and next winter I intend to finish the job by adding a summary of records for each taxon.
A few taxa are still in a holding category. I shall have to make my mind up about these before the final publication.
This will be very much a first attempt. Updates will be needed in the future.