Member’s Evening (via Zoom)
Thursday 8th April 2021
Following the success of our Zoom meetings throughout the winter, it was decided to hold a member’s evening, where members could volunteer to give a short presentation on a topic of their choice, rather like we did at Christmas, but restricting the time to allow for questions and time to chat afterwards. Such was the response from members offering to give presentations that two member’s evenings were planned, one for 8th April and another on 22nd April. The following is a summary of the presentations given on 8th April.
Farr Away in Naver Naver Land by Robert
Robert has visited this site in the north of Scotland near Bettyhill on more than one occasion, with the photographs shown in this presentation mostly from a beautiful sunny day in June 2018. Robert talked a little about the history of the area including the forceful removal of inhabitants from the area in the 1700’s and 1800’s (the Highland Clearances) and showed photographs of some of the plants he found in the coastal heath. These included Scottish Primrose (Primula scotica), Pale Butterwort (Pinguicula lusitanica) and Purple Oxytropis (Oxytropis halleri).
Elm Trees by David N
David talked about the effect of Dutch Elm Disease on Britain’s elm trees (Ulmus spp.) and a report by Future Trees (see link below) on the current situation in Britain.
The report states that before Dutch Elm Disease decimated the British elm populations in the last century, elm was the second most important broadleaf timber tree in Britain, second only to oak. Elm hosts 80 species of invertebrate, notably the rare Whiteletter Hairstreak butterfly. Dutch Elm Disease killed many millions of elm trees, most evidentially seen by the loss of the mature elm trees in woodland and hedgerows and their subsequent replacement by root suckers which grow up for 5 to 20 years before succumbing to disease again. Since the 1990s, it has been apparent that isolated, small populations and individual trees have survived and may be avoiding, or be tolerant or resistant to, Dutch Elm Disease. See the full report: https://www.futuretrees.org/wp-content/uploads/2020/06/Where-We-Are-With-Elm-2019.pdf
David also talked about his personal relationship with the elm and that when he moved to Colne, he plotted the location of Wych Elms (Ulmus glabra) over 6m high in his area, particularly as he was interested in Whiteletter Hairstreaks.
Plants of Halkyn Mountain by Mavis
Halkyn Mountain is an elongated limestone plateau in VC51 Flintshire, in North Wales, near to where Mavis lives. Trial lead pits in times gone by have resulted in the area being covered in grassy hummocks, now heavily grazed by sheep. Calaminarian Grassland generally has high concentrations of toxic heavy metals, often as a consequence of mining and supports a range of metal-tolerant plants, including Moonwort (Botrychium lunaria) and Spring Sandwort (Sabulina verna), both of which Mavis has found at Halkyn Mountain. There are about 12 ha of Calaminarian grassland in this part of Wales, 50 ha in Wales and 100 ha in the UK. Some more of Mavis’s finds at this site:
Green-winged Orchid (Anacamptis morio) – 1 plant found, but then it disappeared (picked/grazed?)
Mountain Everlasting (Antennaria dioica) – hadn’t been seen since 1969 but Mavis found 90 plus flower spikes, all one plant and male. Two weeks later there were only 15 flower spikes.
Dwarf Thistle (Cirsium acaule) – on the Flintshire Rare Plant Register
Autumn Gentian (Gentianella amarella) – last year was a very good year with over 4000 seen across Halkyn Mountain. The sheep don’t seem to eat them.
The site is designated as a SSSI, not for the plants, but for Great Crested Newts. However, Mavis noticed that the ponds are choked with the invasive New Zealand Pigmyweed (Crassula helmsii). Mavis would be interested to see what would grow at Halkyn Mountain if sheep were excluded. Slender St John's-wort (Hypericum pulchrum) manages to survive the grazing by growing up through the gorse.
Not All Flowers by Graham H
Graham showed a range of superb photographs, talking about some of his interesting finds including algae, lichens, mosses, liverworts, fungi, plant galls, ferns and flowering plants. Some examples:
Trentepohlia - an alga that commonly forms large orange patches on tree trunks. The strong orange colour is caused by the presence of large quantities of carotenoid pigments which mask the green of the chlorophyll.
Nettle Clustercup Rust Fungus (Puccinia urticata) - found on the stems and leaves of Common Nettle, producing galls in the form of orange blisters or swellings. The fungus has an over-wintering stage where it infects sedges but without forming galls.
Socket Lichens (Solorina) – distinguished by the large apothecia (spore producing structures) sunken into the surface of the lichen. Graham showed a photograph he’d taken of this at Trollers Gill.
Crescent-cup Liverwort (Lunularia cruciata) – has crescent-shaped receptacles which contain disc-like structures called gemmae, used for vegetative reproduction. Rain drops flick out the gemmae, which if they land on suitable habitat, will produce new plants.
Lemon-scented Fern (Oreopteris limbosperma) – Graham’s photograph showed the oil glands which give the lemon scent when brushed against.
Purple Toothwort (Lathraea clandestina) – found at Adel Dam Nature Reserve. Graham thinks it was planted at Golden Acre Country Park and has washed down from there.
Globeflower (Trollius europaeus) – Many in flower at Ashes Pasture at the end of May. Insects have to push their way through the partly opened corollas.
Spring Flowers by Nyree
Nyree showed photographs of some of her favourite spring flowers and talked about some good locations where they can be found. These included:
Wild Daffodil (Narcissus pseudonarcissus)
Lesser Celandine (Ficaria verna)
Colt's-foot (Tussilago farfara)
Cuckoo-pint (Arum maculatum)
Primrose (Primula vulgaris)
Butterbur (Petasites hybridus)
Giant Butterbur (Petasites japonicus) – seen near Lindley Wood Bridge
Toothwort (Lathraea squamaria) – in Leathley
Bird Cherry (Prunus padus)
Yellow Star-of-Bethlehem (Gagea lutea) – Bruce found a new site near Leathley
Early Dog-violet (Viola reichenbachiana)
Wood Anenome (Anemone nemorosa)
Bluebell (Hyacinthoides non-scripta) – photographed with two orange-tip butterflies
Marsh-marigold (Caltha palustris)
Early-purple Orchid (Orchis mascula) – Oxenber Wood near Austwick
Susan