The Radnorshire Rare Plant Register 2020 Edition
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Subject to revision The Radnorshire Rare Plant Register 2020 edition Comprising records of vascular plant taxon of conservation interest made since 1987 in the Vice County of Radnorshire based on the original by Ray Woods Radnor Lily at Stanner Rocks. Photo by 2016 Editor Polly Spencer-Vellacott 26 /03/20 2020 Editor Barbara Brown Barbara Brown Radnorshire Rare Plants Register 2020 Edition Summary This report collates records made since 1987 of the native and archeophyte vascular plants occurring in Radnorshire which are of conservation concern. Of the 1727 native and archeophyte vascular plant species recorded from the British Isles 1467 have been recorded from Wales (Dines 2008). The Botanical Society of Britain and Ireland lists on its website as recorded from Radnorshire up to the year 2020 a total of 1461 taxa, 875 of which were considered to be native. Most hybrids and apomictic species in the genera Hieracium (hawkweeds), Rubus (brambles)and Taraxacum (dandelions) have been poorly studied in Radnorshire so they are not included here. The neophyte and casual taxa have also been removed but archeophyte species and important hybrids are included. This gives 307 taxa which are included in this report. The results of the analysis have placed the taxa in the following categories (NB; A taxon can occur in more than one category). British Red Data Book Species (RDB) The British RDB lists taxa made up of 2 Critically Endangered, 1 Endangered, 8 Vulnerable and 15 Near Threatened taxa that occur in this Rare Plant Register. In total 8.5% of the vascular plant flora of Radnorshire are placed in a British threat category, substantially less than the 22% of the Welsh flora and 25% of the British flora. Radnorshire has only a low number of British RDB species. Welsh Red Data Book Species The Welsh RDB lists 11 taxa that occur in this Rare Plant Register. This is made up of 3 Critically Endangered, 2 Endangered, 7 Vulnerable and 4 Near Threatened species. Radnorshire has a relatively a low number of Welsh RDB species. Section 7 Species. The Environment (Wales) Act 2016 11 priority species occur in Radnorshire. They occur in a range of habitats with 2 occurring in species-rich unimproved grasslands, 2 in arable fields, 2 in upland pools, 1 in bogs, 1 on a river bank, 1 in upland heath, 2 on open ground and 1 on woodland edges. Vice-County Rarities 128 taxa listed here are Vice County rarities, 83 are scarce at a Vice County level and 34 are nearly scarce. This is calculated by looking at the number of records per tetrad in Radnorshire. 1 Internationally Notable taxa 8 taxa are identified by Cheffings & Farrell (2005) as being of possible international importance. The endemic Whitebeam (Sorbus porrigentiformis) certainly is. More surprising are plants such as Pignut (Conopodium majus) that has a very limited world distribution as does Marsh St. John’s-wort (Hypericum elodes) as well as Ivy- leaved Bellflower (Wahlenbergia hederacea), Ivy-leaved Crowfoot (Ranunculus hederaceus), Round-leaved Crowfoot (Ranunculus omiophyllus) and Meadow thistle (Cirsium dissectum). Other species could be added to this list such as Wilson’s filmy- fern (Hymenophyllum wilsonii), Pillwort (Pilularia globulifera) and Whorled caraway (Trochdaris verticillata) with possibly half the world populations of these species in Britain. The British Isles also supports important populations of bluebell and wild daffodil. The Register This register considers species of flowering plants, ferns and fern allies recorded from the Vice-county of Radnorshire (VC 43) that are believed to be native or archaeophytes (naturalised since before AD 1500). The study of critical genera of the hawkweeds, dandelions, eyebrights, roses and brambles is too imperfect in Radnorshire to permit their evaluation with any confidence. Most hybrids also await detailed study. Why do we need a rare plant register for Radnorshire? The Environment (Wales) Act 20161 sets out Wales’ approach to planning and managing natural resources at a national and local level, enshrining in statute the principles of sustainable management of natural resources. It contains two key sections. • Section 6 - Biodiversity and resilience of ecosystems duty Section 6 of the Act places a duty on public authorities to ‘seek to maintain and enhance biodiversity’ so far as it is consistent with the proper exercise of those functions. In so doing public authorities must also seek to ‘promote the resilience of ecosystems’. The duty replaces in Wales the section 40 duty in the Natural Environment and Rural Communities Act 2006 (NERC Act 2006). Public authorities will be required to report on the actions they are taking to improve biodiversity and promote ecosystem resilience. 2 • Section 7 - Biodiversity lists and duty to take steps to maintain and enhance biodiversity This section replaces the duty in section 42 of the NERC Act 2006. The Welsh Ministers will publish, review and revise lists of living organisms and types of habitat in Wales, which they consider are of key significance to sustain and improve biodiversity in relation to Wales. The Welsh Ministers must also take all reasonable steps to maintain and enhance the living organisms and types of habitat included in any list published under this section, and encourage others to take such steps. Without a work of this nature conservation priorities and the success of measures to ensure Wales develops sustainably cannot be established. The Well-being of Future Generations (Wales) Act 2015 seeks to improve the social, economic, environmental and cultural well-being of Wales. One of its seven well- being goals aspires to: 'A nation which maintains and enhances a biodiverse natural environment with healthy functioning ecosystems that support social, economic and ecological resilience and the capacity to adapt to change (for example climate change).' These worthy aspirations can only be realised if at the planning stage of any development the impact of such a development can be measured and avoided or mitigated. This register is an essential tool if we are to achieve this goal. Radnorshire Vice-county The Watsonian Vice-County of Radnorshire does not exactly follow the Powys Shire Committee boundary of Radnor. It excludes areas at the head of the Elan Valley (in Montgomeryshire V.C.) and around Elan Village (in Brecknock V.C.) and includes part of the parish of Glasbury (in the Brecknock Shire Committee Area). See Woods (1993) for details. Which Species are Included? Species are included for the following reasons:- They are listed either in the UK or Welsh National Red Data Books, the former held on the JNCC website and the latter on the Plantlife website (Dines 2008). Some also occur in the Irish Red Data book. Their national conservation status is abbreviated as follows:- CR=Critically Endangered, EN=Endangered, VU=Vulnerable, NT=Near Threatened, suffixed by the country this refers to eg W for Wales, IR for Ireland. 3 A Vice-County Rarity species has been recorded since 1987 in 3 or fewer tetrads. This is shown in the text by VCR. Vice-County Scarce (VCS) species have been recorded since 1987 in 4-10 tetrads. Vice-County Near Scarce (VCNS) species occur in 11-30 tetrads. The number of tetrads per taxa in Radnorshire has been calculated by using this search query in the BSBI’s database. https://database.bsbi.org/search.php#query=df0ff6357c16c74a8ae45d297e46ba25& savedid=0.16n Many taxa occupy habitats that until recently were much more widespread. The latter half of the 20th century saw the development of agricultural and forestry practices, such as land drainage, regular ploughing and reseeding and the creation of dense conifer plantations that were inimical to many wild plant species such as Dyer’s Greenweed (Genista tinctoria), Wood Bitter-vetch (Vicia orobus), Greater Butterfly-orchid (Platanthera chlorantha) and Moonwort (Botrychium lunaria). Radnorshire probably has over one million sheep (compared to a human population of c24,000). It is not therefore surprising that some species such as Purple loosestrife (Lythrum salicaria), Field Scabious (Knautia arvensis ) and Common Fleabane (Pulicaria dysenterica) have been brought to the edge of extinction in the county by intensive grazing pressure. Some species such as Meadow Thistle (Cirsium dissectum) and Whorled Caraway (Trochdaris verticillata) are included because they have important edge of range populations in Radnorshire. Whilst every attempt has been made to trace records, no complete checked and authenticated synthesis of all the vascular plant records from Radnorshire exists. The editors and recorders have done their best but accept no responsibility for any errors or omissions. Land use changes that might adversely affect a site for a notable species should always be carefully considered and such change only implemented if no alternative course of action can be identified and the action can be demonstrated as being of overwhelming public benefit. The list of taxon included here comes from the previous edition of the Radnorshire Rare Plant Register which was edited by Polly Spencer-Vellacott in 2016, itself based on the 2001 original by Ray Woods. Additions have been made to this via spreadsheet analysis of locally rarer species. This spreadsheet was developed by Andy Amphlett in 2015 and the list derived from the spreadsheet was kindly reviewed by the Elizabeth Dean (VCR) and Ray Woods. Site Visits In the Cardiganshire Rare Plant Register of 2001, Arthur Chater draws attention to the responsibility anyone seeking rare plants owes to landowners and those responsible for the conservation of wild plants. His wise words are reproduced here. “It cannot be 4 too strongly emphasised that most of the sites listed in this register are on private land and should not be visited without permission from the owners or tenants….now that the collection of rare plants is largely a thing of the past, the chief threat to the species in this Register is from unwitting destruction of their habitats.