Tall Yarrow - Achillea distans
Credit for this find should be accorded to the late Mr Frank Kennington who, several years ago, reported seeing a, "queer-looking big yarrow near Welwick Saltmarsh". At that time I found plants that were not exceptionally bigger than yarrow, but certainly had paler green leaves like those of tansy in outline, but were more finely dissected. We agreed that it is probably just a 'sport' of yarrow and I thought no more about it until today, 1 July 2017. Looking through our Atlas 2020 progress maps I noted Achillea distans listed with only one record of the taxon, on West Hull Dock, 1938 (Ref Crackles' flora). I looked for descriptions and images of A. distans on the internet and realised that the Welwick plant is, indeed, A. distans. I took camera and Stace and re-found it scattered among sea couch and bramble along the track from Sheep-Trod lane to Welwick Saltmarsh reserve entrance at TA338191, over a distance of about 500 m. The tallest plant was 1.2 metre high but most were in the range 50 to 80 cm.
Stace says that our plant is subsp. tanacetifolia which correlates well with these plants, but I'd settle for Achillea distans.
Peter J Cook, 1 July 2017
Slender Knapweed - Centaurea debeauxii subsp. nemoralis
This taxon has baffled taxonomists for years. It is the fertile hybrid of C. nigra and C. jacea with all the problems of variations that can result from such a pairing. There are at least 14 different synonyms, four of which have been used to record local occurrences since 1946. For the time being, C. debeauxii subsp. nemoralis is the favoured combination. It was recorded by this name last year in 4 tetrads on Flamborough Head by David Broughton, and by me as C. nigra var. nemoralis near Cottam. In recent weeks I have found it at Haverfield Quarries near Welwick (TA31 and TA32) and near Garton (TA23). I suspect that close examination of knapweeds on dry sandy or chalky soils almost anywhere will yield up more records. For a good close-up photographic identification guide see The BOTANY.cz web pages. The CABI Invasive Species Compendium websitegives a very good account of the taxonomy, identification and differentiation from C. nigra. Happy hunting!
Peter J. Cook, 5 July 2017
An opportunity to record in a square with no post 2000 attention and hopefully boost the hectad score to more than 400 was too good to miss on what turned out to be a nice day out. Most of the village's grassy banks and verges were mown mercilessly short but there was hedgerow, a little-used public footpath, some woodland and a road bisecting the tetrad offering easy access to field margins. A total of 126 mostly banal species was recorded. The best finds were some ferns on an old brick wall and some good woodland plants.
[ I can confirm that, by some strange statistical quirk, our Mapmate database thinks that we now have exactly 400 taxa for TA07! - RM]
Peter J Cook, 03 July 2017
Round-fruited Rush, Juncus compressus
Extra special care has to be taken over differentiating Juncus compressus growing in a brackish habitat from J. gerardii. Several different texts were used to examine specimens of suspected J. compressus found on sandy mud bordering recently (3-5 years) excavated scrapes in the slack of the grey dunes behind Welwick Saltmarsh at TA 337191.
Although partially grazed by sheep so that estimation of total area was not easy, there was approx 0.5 sq m of loosely tufted rush, arising mostly from firm sandy mud but also mixed with young shoots of Bolboschoenus maritimus. Fruiting stems were 8 to 10 cm tall and conspicuous by their large, shiny, spherical fruit exceeding the perianth by about 1/3rd of the capsule diameter. Perianth segments are light brown (not dark brown as in J. geradii) and are broader and more rounded at the tip than in that species. Mature capsules are much darker than the perianth segments and the specimen in the photo is immature. The lower stem is round, not slightly 3-angled as described for J. gerardii in some texts, and is flattened below the inflorescence. The identity was confirmed in the measurement of the seeds which are less than 0.5 mm, and in some plants (e.g. photo) the lowest bract over-tops the inflorescence. Leaves are basal and flat in both species and glaucous in J. compressus. Note that J. compressus is also being found on road verges.
Peter J Cook, 2 July 2017
A serendipitous shot
My son, Matthew, spotted a colony (swarm?) of bee orchids on private land in Keyingham, TA22, and took this photograph with his mobile phone. Unknown to him was the significance of the perfoliate plant adjacent to it. Yellow-wort, Blackstonia perfoliata, is always worth looking for near bee orchids - and vice versa - as they seem to be inseparable bed partners.
Peter J Cook, 20 June 2017
Our Local Group was pleased to have Mr Chris McGregor of Natural England accompany us on our visit to this Hull Headwaters SSSI making a total of nine persons. The marsh is sallow and alder carr on the floodplain of the river Hull and tributary chalk streams to the west of Sunderlandwick. It is a site that has had infrequent detailed botanical surveys, the last one being a National Vegetation mapping exercise six years ago, which included only cursory notes of notable field layer species. Within seconds of setting foot into an area recently cleared of sallow, we found tussocks of sedge. Historically there has been dispute as to the identity of tussock sedges at Kelleythorpe and this continues! We decided to refer to expert opinion and moved on.
Sedges were the talking point for most of the visit as we encountered several different ones not commonly encountered including Carex elata, and a tussock of putative C. diandra which is also to be checked. The area is also known for C. acuta and C. rostrata, both of which escaped our attention. This marsh is one of only two known stations for Marsh-fern, Thelypteris palustris, in vc61. So often we have to search for rare plants but here we were amazed to find ourselves in an area where the field layer was a sea of fronds interspersed with sedges and beds of Iris pseudacorus.
Our recording was confined to the SSSI and totalled 77 taxa.
Peter Cook, 15 June 2017
Wayrham - SE85
The BSBI Local Group meeting at Wayrham turned out to be a rather low-key event with our numbers severely depleted by member's work and holiday commitments. Never-the-less Gabrielle and I managed to make a decent impression on tetrads I and P. Our efforts were augmented with lists for Fordeham Dale made the previous (very wet) day by Gabrielle and John K.
By coincidence, the lists for both tetrads ended up at about 100 taxa each, with similar but not identical plants. We found many of the familiar chalk favourites, Betony (above), Rock-rose, Dropwort, etc. but did not manage to record Clustered Bell-flower or Felwort.
Although we made good upgrades to the individual tetrad totals, our impact on the hectad was small - four new taxa raising the total to 429. Of the new plants, three where found in "Bradeham Well", a small valley-bottom pond; Glyceria notata, Potamogeton natans and Lemna minor the fourth Thlaspi arvense was found as a weed in a Phacelia conservation strip near Gill's Farm. Looking on the bright side, it does demonstrate that our sampling strategy over the last few years has been effective and we have managed to paint the big-picture!
Richard Middleton, 13 July 2017
Lemna minor / Lemna minuta
It is always worth looking closely at Duckweeds. The alien Lemna minuta (Least Duckweed) seems to be becoming rather common and widespread within the county and has probably been under-recorded. The above image shows a couple of fronds of Lemna minor from my garden pond (left) and a sample of Lemna minuta from a pond at Eastrington (right). At Eastrington the alien duckweed was completely covering the surface of a heavily shaded, lowland pond but only a week or so before I had seen it covering the surface of an exposed Wolds "dew pond" at Fordon. The small size of the fronds - generally arround 2mm - is characteristic.
Richard Middleton, 10 July 2017
Frog Rush sequel - Where from?
While looking for something else I found an article by M Wilcox in BSBI News 128 p 25 which puts flesh on one tentative answer to the question arising from my news item of a few weeks ago, i.e., where did the seed come from? It seems pretty obvious that the seed came in on salty water from car tyres but may also have arrived with the gravel used to surface the drive.
Mr Wilcox found Frog Rush on the verges of roads in 31 monads around Dent and Ribblesdale and in VC62 near Goathland. Local searches where we know Spergularia marina and Puccinellia distans to grow may be fruitful.
Peter J Cook, 21 June 2017
Juncus ranarius - an inland record
Frog rush, Juncus ranarius (or once J. ambiguus), is rare in vc61. This is due to the rarity of mud by brackish pools so recent records are for the outer Humber estuary in the Spurn area. Reference to current BSBI maps shows a scattering of inland records in England, though none yet for vc61.
Recently I observed short (2-4 cm) tufts of a mahogany-coloured plant growing on muddy, compressed gravel in the back yard of a house in Keyingham, TA22. They were found where a parked car drips road-salt to form a pool of saline that slowly evaporates - a mimic of the natural habitat for J. ranarius. Many small plants were growing together where they could get a foot-hold between pebbles and present a tufted appearance. Closer examination revealed the distinctive truncate seed capsule, emarginate inner tepals with rounded tip and mucro, and brown colouration with red basal sheaths.
I believe this to be the first non-coastal record for vc61 and suspect that it might be more widespread, indeed, it could be found anywhere where there is likelihood for pooling of salt water.
Peter J Cook, 10 June 2017
Tussock sedge, Kelleythorpe
14 June 2017
Hagg Wood revisited ...
In his earlier note Peter mentions the healthy field discussions which arose on our recent visit to Hagg Wood. The horsetail debate was to continue for some time by e-mail. None of us was happy with a simple solution and a consensus of hybridity was finally agreed upon - Equisetum x litorale being the preferred taxon. By chance the British Pteridological Society were conducting their AGM in Hull last weekend so Gabrielle volunteered to collect material which could be looked at by the experts. I am delighted to announce that Pat Acock has examined Gabrielle's specimen and pronounced our diagnosis to be correct.
This is the first vice-county record of this hybrid for some time. Now we know it's about we will need to take more care to record what is probably an overlooked taxon.
Richard Middleton, 28 April 2017
SE65W - Hagg Wood, Dunnington
This tetrad is on the western outer limit of vc61 and is one of the last remaining target tetrads in a hectad predominantly within the adjacent Vice County and occupied largely by the City of York. It has a wide range of broad habitats including standing and flowing fresh water, marsh and rush mire bordering rides through coniferous woodland, arable fields and mixed species hedgerow. Bracken and Rhododendron understorey covered extensive areas of Hagg Wood in the eastern half. Highlights of the day included monoecious Nitella flexilis, our first stonewort record at Local Group meetings. A fallow arable field was notable for both Viola tricolor and V. arvensis with numerous sizes and colour combinations. The terrestrial form of Bulbous Rush Juncus bulbosus with its neat circular tufts; Bog Stitchwort Stellaria uliginosa with its elastic stele; violets prompting differentiation between V. riviniana vs. reichenbachiana vs. odorata; a horsetail emergent from water 'behaving badly' for both Equisetum palustre and E. fluviatile and leaves of Leopard's-bane Doronicum pardalianches each resulted in 'diagnostic huddles', and proved necessity to carry vegetative keys at least in Spring.
Five pairs of eyes recorded 170 taxa which is considered good for an early April outing.
Peter Cook, 13 April 2017
Dipping a toe into rhodology
Armed with Roger Maskew's, "New dichotomous key to native and alien species of Rosa L." (BSBI News 135, pp 46-48) I took my first step into identifying roses with some interesting results. I chose a section of the dismantled Hull-Hornsea railway just South of New Ellerby in tetrad TA13U and found three different taxa. Once I had identified them in the field using the new key, I sampled them for cross-examination at home using G.G. Graham and A. L. Primavesi, (BSBI Handbook 7). Then I checked for prior record and was pleased that all three taxa had been recorded in vc61 before, albeit with alternative nomenclature, though not in Hectad TA13. I am happy to pronounce the following taxa: Rosa caesia x R. canina; Rosa squarrosa (Glandular Dog-rose) recorded previously as R. canina L. group Dumales, and Rosa canina L. (already recorded as R. canina Group Lutetianae or Group Transitoriae - these two groups are now 'lumped'). Under 'pre-lumped' nomenclature my record would have been R. canina Group Transitoriae, which appears to be the most commonly recorded Dog-rose taxon.
We have a lot of work to do on roses. I found this new key very easy to use and commend it. Secateurs and gloves are advised. Good luck!
Peter J Cook, 11 August 2017
In June 2011 Cedric Gilling found plants of Fumaria vaillantii (Few-flowered Fumitory) growing in set-aside at Fordon. It was associated with F. officinalis (Common Fumitory) and the Nationally and Regionally scarce F. parviflora (Fine-leaved Fumitory). At the time its identity was confirmed by Rosemary Murphy, the BSBI referee and Handbook author, and it became vc61's only record of Britain's rarest Fumitory. A recent visit to Fordon by the combined might of the Hull Natural History Society, Ryedale Natural History Society and the YNU Botany Section provided an opportunity to check on the taxon's survival. Having never seen the plant before I adopted a "shotgun" approach and collected representative samples from the spectrum of Fumitories growing in what is now a sparse rape field, with the hope of bagging a "vaillantii".
After a couple of hours with Stace, the BSBI Handbook and a microscope, I am now confident that we located all three of the Fumitories found by Cedric in 2011. The above composite picture shows individual flowers from (top to bottom) F. officinalis, F. parviflora and F. vaillantii. The larger flower of F. officinalis and the colour difference between F. parviflora and F. vaillantii is at once apparent. Confirmation of F. vaillantii is afforded by the minute stipule (barely visible on the photograph) and a bract less than half the length of the fruiting pedicel (not shown but it was there!)
The origins of this decidedly southern arable weed remain unknown but it was definitely thriving on this thin, dry, chalky soil in the company of the largest concentration of Ranunculus parviflorus (Small-flowered Buttercup) that I have ever seen. Other companions from our Rare Plants Register included Legousia hybrida (Venus's-looking-glass), Stachys arvensis (Field Woundwort) and Torilis nodosa (Knotted hedge-parsley).
Richard Middleton, 28 June 2017
SE64T - Wheldrake Wood
After one of the driest Aprils on record and an equally arid start to May, we were treated to a restoration of nature's fluid balance. Despite the rain, four stalwarts (?) proceeded with the planned exploration of Wheldrake Wood in steadily deteriorating weather and although the conditions were not conducive to overt enthusiasm we did enjoy several hours of interesting botany; John's knowledge of forestry trees bumping up our list of conifers considerably. With the exception of some Marsh Orchids and a couple of plants of a steroid-fuelled Geum (provisionally identified as G. macrophyllum, see picture), we didn't find anything particularly exotic but with a total of over 130 taxa we were well satisfied with our expedition.
Richard Middleton, 19 May 2017
How many fingers?
Yellow may normally be considered the colour of Spring but for the urban botanist it is certainly white. The pavement cracks and corners are now full of small white-flowered plants which can look remarkably similar from a distance - Bittercresses, Thale Cress, Whitlowgrass, Scurvygrass, Shepherd's-purse, etc. Yesterday morning I encountered a dense patch of such plants on the corner of Charlotte Street and Grimston Street, Hull. Very closely crowded and low-growing I did not recognise them immediately so took a small specimen in the hope of Cerastium semidecandrum. Careful examination at home revealed fleshy spathulate leaves,a dense covering of red-tipped hairs and short blunt sepals - Saxifraga tridactylites. (picture - mm scale)
Ironically, just before encountering the plants I been looking at a fine display of typical Rue-leaved Saxifrage only 100 metres away - the plants discovered last year by Gabrielle! The confusion arose as none of the plants in this new colony bore the "typical" (but clearly not obligatory) three fingered leaves.
Richard Middleton, 4 April 2017
John Killingbeck and Gabrielle Jarvis have made an interesting discovery in Hornsea this month - Cyrtomium falcatum (House Holly-fern) growing with Asplenium scolopendrium (Hart's-tongue) on a shady wall. It would be very easy to overlook this alien fern which is a relatively recent addition to our vice-county's flora.
Richard Middleton, 14 March 2017