Tuesday, 12 August 2014

Hybrid thistle

Having finished writing a long report, I was in need of some fresh air, so pottered off to Castor Hanglands. I wasn't really botanising, just trying to clear my head, but I then spotted a thistle that looked odd. The flower structure was like Cirsium arvense, but a somewhat deeper and redder shade of purple than usual, and the stem was partially winged. It was growing close to a patch of C.arvense, but there was also a very typical C.palustre growing close by.

Winged stem

Reddish-purple flowers

The intermediate features fit the hybrid between C.arvense and C.palustre, which goes by the snappy name of C. x celakovskianum. It seems to be a fairly rare cross, and doesn't seem to have been recorded from VC32 before, though I don't suppose many people look that hard at thistles!

False grass-poly

I've been very engrossed in report writing, so field time has been limited. Nevertheless I was surprised to find a plant I didn't recognise at all on a quick dog-walk to Ferry Meadows. It was growing in a shady area along the old route of the A47. At first glance I thought it might be a weird purple loosestrife Lythrum salicaria, but there were only one or two flowers in each axil. In Stace it keys out to false grass-poly Lythrum junceum, a casual bird-seed alien, though I have to say it was an unusually robust specimen. Certainly people do scatter bird seed close-by, and this could be the source. It seems to be only the second record for VC32!

Saturday, 2 August 2014

A multitude of mulleins

Recently I've been working on some land close to the East Coast mainline, which is one of the richest sites I know for mulleins. These can be rather puzzling, as like many taxa, they hybridise freely. So far I've recorded at least nine taxa, although only eight this year. These include:

Great mullein Verbascum thapsus

This is by far the commonest species, and has the anthers of the two lower stamens asymmetrical, branched hairs, decurrent leaves and a capitate stigma. All the hairs on the anthers are white and it normally has an unbranched inflorescence.

Dark mullein Verbascum nigrum

Once again the flowering stem is usually simple or sparsely branched but the anthers are all reniform and symmetrical, many hairs on the filaments are violet, there are several flowers per node and each pedicel has two small bracteoles, the pedicels are of variable length and the bases of the leaves are cordate.

Verbascum x semialbum (V. thapsus x V.nigrum)

This is by far the commonest hybrid in the genus and is quite frequent where both parents occur. All anthers are reniform and symmetrical, and usually the upper 3 filaments have violet hairs and the lower 2 white hairs, though there can also be a rather more random mix.

Hoary mullein Verbascum pulverulentum

A local species of East Anglia, whose spectacular branched inflorescences can often be seen on road verges, particularly along the A14 in Suffolk and the A47 round Norwich. The anthers are all reniform and symmetrical, and the filaments have dense white hairs. The leaves are are mealy and the hairs gradually rub off (they're also very irritant!). This one is pretty unmistakable.

Verbascum x mixtum (V.nigrum x V.pulverulentum)

A rare hybrid with the spectacularly branched inflorescence of V.pulverulentum, but with a mix of purple and white hairs on the filaments of the anthers, which are all reniform. The leaves are softly hairy, with some purple colouration along the main vein.

Caucasian mullein Verbascum pyramidatum

Superficially quite similar to V. x mixtum in the branched inflorescence and presence of violet hairs on the filament. However, there is only one flower per node in the axil of the bract, with no bracteoles and the leaves have a very different texture, being rather crinkled.

Twiggy mullein Verbascum virgatum

This is possibly native in the west country, but is a fairly frequent casual of waste places elsewhere. The anthers are asymmetrical, the stem has glandular hairs for the whole of its length and the inflorescence is usually simple with yellow flowers and violet hairs on the filaments. The main characters separating it from moth mullein V.blattaria are that there are usually more than one flower per node in the lower part of the inflorescence and the pedicels are mostly shorter than the calyx.

White mullein Verbascum lychnitis

A rare species of southern England, which is also occasionally established on brownfield sites. The anthers are reniform and all the hairs on the filaments are white. The flowers are normally white (although they can be yellow) and the inflorescence is usually branched although it may be feebly so in stunted specimens.

Monday, 21 July 2014

Pain-free nettles

If you're by a river bank or in a fen, keep a look out for stinging nettles with particularly long, narrow leaves. And then if you're feeling brave, try brushing your hand against them. The chances are you won't be stung, as this leaf shape is very characteristic of Urtica dioica subsp. galeopsifolia, the stingless nettle.

The classic locality for this subspecies is Wicken Fen, but it occurs more widely in damp habitats. The images above were taken on the bank of the River Nene at The Boardwalks LNR, where it occurs alongside the normal painful nettle, as well as with some intermediates.

If you examine the leaves closely you'll find that there are scarcely any stinging hairs, but instead there is an indumentum of dense simple hairs. The lowest flowering branches are at nodes 13-22 and it flowers from mid-July onwards, about a month later than common nettle. 

Saturday, 28 June 2014

The Local Patch

Spent a few hours today recording in my local tetrad TL19U, visiting Thorpe Hall Grounds, Holywell Fish Ponds and several local streets. Lots of interesting finds, taking my total to somewhere over 370 species. Highlights so far include:

A good population of bee orchid Ophrys apifera at Thorpe Hall, with more scattered records from Thorpe Meadows

A single pyramidal orchid Anacamptis pyramidalis at Thorpe Hall

A strong population of salsify Tragopogon porrifolius in rough grassland at Thorpe Hall

A few plants of spring beauty Claytonia perfoliata in secondary woodland at Thorpe Hall

A small population of motherwort Leonurus cardiaca at Thorpe Hall

Moth mullein Verbascum blattaria at Thorpe Hall

Deadly nightshade Atropa belladonna in an area of secondary woodland at Thorpe Hall

A strong population of black mullein Verbascum nigrum on disturbed ground (possibly archaeological diggings) at Holywell Fish Ponds, growing not far from a very large population of whorled water-milfoil Myriophyllum verticillatum in one of the ponds.

Several bushes of the hybrid Salix x smithiana (S. viminalis x S.caprea) at Holywell Fish Ponds, only known from nine other sites in VC32

A single bush of white barberry Berberis candidula naturalised in a shrubby area of Holywell Fish ponds - possibly new to VC32

A good population of creeping bellflower Campanula rapunculoides in an area of waste ground in Netherton - possibly a new record for VC32

A good population of Balkan spurge Euphorbia oblongata (another possible new VC record) in the same area of waste ground, where there was also cotton thistle Onopordum acanthium and large-flowered evening-primrose Oenothera glazioviana.

Wednesday, 25 June 2014

Swaddywell Pit

I followed Bob's advice and headed off to Swaddywell Pit this morning to see the spectacular display of pyramidal orchid Anacamptis pyramidalis - well worth a visit and very close to the car-park if you're short of time!

Lots of other interesting species flowering too including lots of lesser centaury Centaurium pulchellum and brookweed Samolus valerandi in a damp area of compacted clay.

Centaurium pulchellum

Samolus valerandi

Wednesday, 18 June 2014

Grimsthorpe Park

The South Lincolnshire Flora Group had an excellent afternoon recording the parkland of the Grimsthorpe Estate. There were many good records, including Pale Sedge Carex pallescens and Grey Sedge Carex divulsa subsp. divulsa, both growing along bracken fringed paths, rather than their more usual woodland ride habitat. Both species are very local in South Lincolnshire.

Carex pallescens
A small group of us stayed on to record around the Stew Ponds, and on our way dropped in at Elsea Pit to see the Early Gentian Gentianella anglica, which seems to have had a good year. This endemic species is rather like Autumn Gentian Gentianella amarella, but flowers considerably earlier and the distance between the two uppermost leaf pairs is 40% or more than the height of the plant.

Gentianella anglica
We were almost running out of time, so our visit to the southern edge of the Stew Ponds was rather brief, but it was very pleasing to find a large population of Round-fruited Rush Juncus compressus, which is a much declined species (GB RedList near Threatened) and appears to be a new record for the estate.

Juncus compressus

Tuesday, 10 June 2014

Grass vetchling galore

I spent a long day on a site in Hertfordshire. The highlight of the visit was finding an extraordinarily large population of grass vetchling Lathyrus nissolia, which is one of my favourite species. The intensely bright pink flowers are unmistakable, but the foliage is so grass-like that this species is almost impossible to record when it's not flowering. I'm amazed I managed to get a decent image, as there was a strong breeze blowing all day! This very southern species favours disturbed habitats, particularly on calcareous clay, and seems to have spread recently, possibly because it is sometimes included in commercial seed mixes.

It was also good to see a very good population of wood speedwell Veronica montana in the ancient woodlands. This species is easy to identify when the pale lilac flowers are visible, but can sometimes be overlooked as germander speedwell Veronica chamaedrys when it's in the vegetative state. However, the latter species normally has two lines of hairs on the stems, while V.montana has the hairs evenly distributed around the stem.

Sunday, 8 June 2014


I finally felt well enough to risk a trip to one of my Lincolnshire priority tetrads. I chose Skillington, as there seemed to be a rather nice Drove Road along the county boundary, that I suspected might have some good calcareous grassland. It had rained heavily the day before, and when I finally arrived my heart sank as it was fringed with scrub and the centre of the track was deeply rutted with deep muddy puddles. Nevertheless, I persisted and a little way along the track there were some good areas of grassland, with locally frequent woolly thistle Cirsium eriophorum  and a suite of other calcicoles including upright brome Bromopsis erecta,  salad burnet Poterium sanguisorba, bird's-foot-trefoil Lotus corniculatus, burnet saxifrage Pimpinella saxifraga, greater knapweed Centaurea scabiosa and a small population of rock-rose Helianthemum nummularium. There was also a lot of common knapweed Centaurea nigra, as well as some unusually slender forms with cut leaves. Unfortunately they weren't in flower, but the shape of the phyllaries on the bud seemed a good match for chalk knapweed Centaurea debeauxii, which would be a first record for VC53. A return visit will be required!

Helianthemum nummularium
Eventually I was stopped in my tracks by a very deep puddle, so I turned back, recorded a stretch of roadside verge and then had a walk around the village, which added a lot of garden escapes and other usual village denizens. A white Geranium had me puzzled, but in the end I managed to identify it as a white form of hedgerow crane's-bill Geranium pyrenaicum, which had escaped from a nearby garden. There was also a very fine display of purple crane's-bill Geranium x magnificum along a road bak.

Geranium pyrenaicum ' Alba' or 'Snow in Summer'

Geranium x magnificum