Tuesday, 29 July 2014

X Agropogon robinsonii & others, National Botanic Garden of Wales

A visit to the gardens during last week's heatwave roved productive with a couple of cudweeds, a spurge and a intergeneric grass hybrid.

Polypogon viridis is now among the most common grasses around the propagation glasshouses at the gardens. Reasoning that this increased my chances, I set to hunting for its intergeneric hybrid with Agrostis stolonifera: Agropogon robinsoniiDespite somewhat conflicting literature including what appears to be an erroneous description in Sell & Murrell I managed to find a single putative hybrid plant. Examination back home under the microscope showed a mixture of characters of the two parent species and intermediate character states. The anther length (c. 1.1mm) being closer to A. stolonifera and much longer than that of P. viridis (c. 0.6mm). The lemma and palea resembling those of P. viridis both in shape and relative length (almost equal). The glumes having sparse scrabidity from P. viridis but more pronounced bristles on the keel from A. stolonifera. The end of the ligule  being ciliolate as in P. viridis but the overall structure of the tiller more like that of A. stolonifera. Given these features I'm happy to call the plant X Agropogon robinsonii though it will probably need to be sent off for confirmation. As far as I can tell this hybrid has previously only been recorded four times in the UK (all but one in the Channel Islands) and once in France. Given the rapid spread of P. viridis in recent years it may be that other people have found this hybrid recently. If not it is probably worth keeping an eye out for wherever P. viridis occurs.

***Note***  Now 'cautiously confirmed' by Tom Cope at Kew as the fifth ever record of this taxon. The 'cautious' prefix having to do with some previously confirmed material of this this taxon having been redetermined as pure Polypogon and the fact that the only other available material (a Guernsey collection from 1997 by Rachel Rabey) is much larger and more distinctly intermediate between the parent taxa than NBGW material. On balance however the male sterility and persistent glumes were, according to Tom Cope, enough for the 'cautious confirmation'. Confirmation is with thanks to Richard Pryce, Arthur Copping, Tom Cope and Rachel Rabey.      

Agropogon robinsonii, culm,
NBGW, SN 52105 18410

X Agropogon robinsonii, habit,
NBGW, SN 52105 18410

Agropogon robinsonii, tiller,
NBGW, SN 52105 18410

Agropogon robinsonii, inflorescence,
NBGW, SN 52105 18410

Now cudweeds, the most interesting of which was a single plant of Gnaphalium luteoalbum growing on gravel between two propagation glasshouses. This species is restricted as a native to a few sites in the south of England and occurs as a scattered casual elsewhere but appears not to have been recorded in Wales post 1930. Despite fairly extensive searching I could not locate any more plants suggesting that this species may have only just arrived at the gardens.

A more frequent cudweed: Filago vulgaris was abundant on on parched ground around the science block. Bringing the cudweed total for my trip to three including the common Gnaphalium uliginosum.

Gnaphalium luteoalbum,
NBGW, SN 52138 18412

Filago vulgaris,
NBGW, SN 51970 18239

Finally a spurge: Euphorbia stricta is very local as a native being restricted to the open ground in woodlands around the southern Welsh borders. At the gardens it grows in abundance behind a single polytunnel. I don't know if it arrived at the site of its own accord as a casual or, more likely, either as a horticultural species or as part of the Garden's Welsh Rare Plants Project.

Euphorbia stricta,
NBGW, SN 52053 18410

Greater spotted woodpecker, dead from flying into glasshouse,
and a calliphorid fly, NBGW

Monday, 30 June 2014

Spring: Hectic Catch Up

Spring has passed and I have not produced a single post. So here, cobbled together without any real narrative, are some of the pictures I've amassed over the past months. 

For continuity we return where winter left us in the Aberystywth University Vice-Chancellor's garden where, in March, a strange parasite pokes artificial looking purple and white buds through the leaf-litter. Lathraea clandestina is an alien that mostly occurs in gardens and is scattered across the UK. In Aberystwyth it grows at the base of a Metasequoia glyptostroboides a species that is not thought to be a host though the population is not far from its more generally favoured Salicaceous hosts. 

Lathraea clandestina, buds,
SN 59354 82044, March 2014

Lathraea clandestina, flower,
SN 59354 82044, March 2014

And so spring continued and I briefly left the safety of Aberystwyth for a trip north-east to The Ecological Genetics Group Conference in Newcastle. The second day of the conference saw us escape the confines of the hotel and head out to the remains of an old open cast coal mine near Hauxley. It had, as is often the case with old mine workings, been turned into a nature reserve featuring scrapes and hides. The botany was limited and despite the visit being lead by John Richards (of which more later) not a single Taraxacum was investigated. One very large species that was new to me and admired by all for its architectural qualities was Dipsacus laciniatus an uncommon alien of waste places.     

Dipsacus laciniatus, Spring rosette
NU 28323 02379, 14/04/2014

Dipsacus laciniatus, Old heads, 
NU 28323 02379, 14/04/2014

Shortly after returning from Newcastle I travelled to North Wales with Andy Jones for the BSBI Taraxacum Workshop. With events like this somewhere after the fifth or sixth micro-species and its accompanying explanation you begin to realise that you're fighting a loosing battle, characters and names blur, until, eventually, most that remains is an mental soup of undifferentiated Taraxacum. However John Richards descriptions were informative and often amusing. A favourite statement, acquired from the Danish Taraxacologist Hans Øllgaard, being 'ah, lovely, pedagogic material'. Pedagogic in this sense apparently meaning 'exemplary'. The etymology of which I presume is related to the specimen being perfect for demonstrating the characters of the species. Anyway despite the information overload I did pick up a few species. Taraxacum britannicum a section Celtica species with small involucres with dark tips and erect or adpressed bracts in bud. Taraxacum argutum a section Erythrosperma species with closed capitula and inrolled reddish ligules. Taraxacum insigne a section Ruderalia species with long spoke-like bracts held at right angles to the bud. So three of the 230 or so UK Taraxacum species are now part of my botanical repertoire which is a start I suppose...

Taraxacum britannicum, Treborth, VC49, 24/04/2014

Taraxacum insigne, Aberffraw,
VC52, 25/04/2014

The second Taraxacum day began with a visit to Newborough Warren. Some amusement was had when John Richards initially misidentified what he soon realised to be 'his dandelion' Taraxacum richardsianum. A few plants of this section Nervosa species with its spotted leaves grew in a sandy scrape beside the path. As we picked our way through a minefield of dog poo that spreads out from the car park our Taraxacum list grew with most species turning out to be new county records.

Huddling Taraxcicologists, Newborough Warren, VC52, 25/04/2014

Taraxacum richardsianum, Newborough Warren, VC52, 25/04/2014

As we eventually left the path and headed onto the dunes it began to rain and with lunch time fast approaching it was decided that retreat was the wisest option. Before we turned back we added a few delicate Taraxacum sect. Erythrosperma species including the widespread T. oxoniense with its pale bordered bracts. Other spring sand dune flowers were also in abundance including Vicia lathyroides and the dwarf Valerianella locusta var. dunensis

Taraxacum oxoniense, Newborough Warren, VC52, 25/04/2014

Vicia lathyroides, Newborough Warren, VC52, 25/04/2014

As we headed back I made a last effort to find one of the target species for our visit to Newborough. Taraxacum palustre a member of section Palustre and one of the more easily identified Taraxacum species. Local and closely associated with damp calcareous situations Anglesey is one of its strongholds and there were old records for Newborough. Searches in the tall vegetation during the morning had failed to reveal anything but in eventually in short grazed turf I and another member of the party found two small populations. The majority of the plants were clinging to tussocks of Schoenus nigricans. A particullary picturesque one of these showed nicely the closely appressed bracts and undivided leaves that make section Palustre 'unmistakable' in dandelion terms. 

Taraxacum palustre, Newborough Warren, VC52, 25/04/2014

Our last stop was a seemingly unremarkable lane leading up from the edge of the Menai Straits at Foel Farm. By this point I had seen far too many Taraxacums to assimilate any related information. As we were about to leave Richard Price spotted a single plant of Fumaria purpurea in the hedge bank. It turned out to be a noteworthy end to the day as the species had not been recorded from the county for many years.

Fumaria purpurea, Lane near Foel Farm, 
VC52, 25/04/2014

The day after I returned from North Wales and with Taraxacums still plaguing my every waking thought I shipped out to Preston Montford in Shropshire to assist on a University field course. It was a busy week of varied tutorials covering ecology, geology and land-use with eighty undergraduates. Plants had their place and even took centre stage on a few of the days and we saw a few interesting species along the way.

John Warren demonstrates Equisetum spore movement,
The Ercall,  SJ 64425 09556, 29/04/2014

The first afternoon was spent in Ashes Hollow, in a small stream that flows down the east flank of Long Mynd into Little Stretton. While not strictly botanical I did get to indulge my intermittent interest in Coleoptera when a large and distinctive looking Staphylinid with a fine golden pubescence flew into the side of my head. Later research revealed it to be Ontholestes tessellatus a widespread but not common species associated with dung and carrion.  

Ontholestes tessellatus, Ashes Hollow,
Shropshire, SO 42625 93068,
Coll: 27/04/2014

Emperor Moth (Saturnia pavonia),
Barrister's Plain, Shropshire, SO 42600 92750, 27/04/2014

Returning to the minibuses atop Pole Bank John found Teesdalia nudicaulis growing on a knoll by the car-park. This diminutive Crucifer with its neat little spathulate leaves grows in very dry nutrient poor places and is uncommon in the West.  

Teesdalia nudicaulis, Pole Bank,
Shropshire, SO 41741 94305, 27/04/2014

Later days of the trip included visits to a number of other small hills south though Shropshire as well as the Fens to the north. On the penultimate day we visited the Iron Age fort of Nordy Bank in the Brown Clee Hills. The impressive earthworks atop the small hill supported some nice species including Moenchia erecta, Trifolium micranthum and many little Taraxacum sect. Erythrosperma that were still a mystery to me. 

Moenchia erecta, Nordy Bank,
Shropshire, SO 57469 84752, 30/04/2014

On the last day we climbed the Stiperstones to look at heather cycles and moorland management for grouse. We passed through some nice fields of upland acid grassland dotted with dewy Viola lutea. In the patchwork of managed heather we stopped to set up basic quadrats and record the handful of species present among which were flowering Vaccinium vitis-idaea and the bronze shoots of  Melampyrum pratense.   

Viola lutea, Stiperstones,
Shropshire, SO 36285 98816, 01/05/2014

Vaccinium vitis-idaea, Stiperstones,
Shropshire, SO 36298 99357, 01/05/2014

So that's spring. Hopefully I'll manage more regular updates for the remainder of the season...

Monday, 13 January 2014

The Vice Chancellor's Shrubs

I started this post a few months back, before the rush of my MPhil write-up, now I come back to it and find it to be somewhat unseasonal but given that I have little else to post I may as well complete it.

Around the end of October, a few weeks after my stipend came through, I treated myself to a few of the books I'd ogled on Summerfield Books in the months prior. Among these was the (relatively) recent Cotoneaster monograph by Fryer and Hylmö. An impressive book, designed for gardeners but including keys, comprehensive descriptions and lots of photos. The Saturday after it arrived I wandered up the steepest road in Aberystwyth and into Penglais woods. Passing a few bushes of the frequently naturalised  Cotoneaster simonsii scattered along the path-side I dropped down a zigzag path into the Vice-Chancellor's garden.

The gardens sits between the woods and a small stream, protected from the road and the woodland path by thick growths of Cherry Laurel. Little evidence of its origins as a formal garden organised by plant family remains. An unkempt shrubbery separates the small lawn in front of the house from the bulk of the garden, completely hiding it and creating a nice spot for an summer afternoon's wine picnic or an autumn Cotoneaster hunt.

Before diving into the Cotoneasters I pushed through a flowering female bush of Ilex × altaclerensis a frequently cultivated hybrid between the native I. aquifolium and I. perado, a species from The Azores.

Ilex × altaclerensis, SN 59281 82100

Having not taken my shiny new book out into the field (or garden) I was simply equipped with a knife and a crumpled Lidl bag. This I rapidly filled with a wealth of berry-laden branches. The first of these turned out to belong to Cotoneaster gamblei, its dirty pink berries already having suffered considerable thrush damage. This is a member of the subgenus Chaenopetalum characterised by simultaneous flowering across the whole plant, spreading petals and having the style remnant attached at the tip of the nut. Most of these species are larger than those in subgenus Cotoneaster with some such as C. strictus, the second species I collected growing into medium sized trees with impressive curved trunks.

Cotoneaster gamblei, SN 59333 82073

Cotoneaster frigidus, SN 59333 82073

These two large species were followed by myriad confusing smaller species many of which defied identification either through careful keying or casual flicking through pictures. A few however were more considerate among these were C. capsicinus a species with mucronate tips to the leaves and sparse, singly produced berries.

Cotoneaster capsicinus, SN 59567 82094

Cotoneaster capsicinus, SN 59567 82094

A tall, long-leaved and somewhat scratty bush with single, long, almost black berries turned out to be C. otto-schwarzii & while a bush with deeply-veined uppersides to its leaves and strikingly white-floccose undersides was C. sternianus.

Cotoneaster otto-schwarzii, SN 59583 82069

Cotoneaster sternianus, SN 59347 82139

Cotoneaster sternianus, SN 59347 82139

Crossing the road onto the campus proper my bag was beginning to overflow. Among the few remaining species for which I established a satisfactory determination were the long-leaved C. salicifolius and its very common and variable horticultural hybrid with C. frigidus; C. × watereri.

Cotoneaster salicifolius, SN 59444 81875

Cotoneaster × watereri, SN 59444 81875

All in all there was a huge variety of Cotoneaster taxa present in the small corner of campus that I collected from of which only a handful yielded to my (admittedly novice) identification attempts. In my wanders around other parts of the campus and town in the intervening months I've noticed still more species in various states of denudation. Over the next few years I'll hopefully have the chance to tackle some more of these both in flower and fruit and perhaps, gradually, come to terms with this complex genus.