Monday, 29 February 2016

Hollinhurst Wood to Swillington Park

I made good use of the extra day this month to walk over to Great Preston (VC64) in the last of the sunshine before the rains return. Hollinhurst Wood turned up a few new species that I had not had previously for the site and/or the hectad. These included naturalised Box-leaved Honeysuckle (Lonicera pileata) and Highclere Holly (Ilex x altaclerensis). The latter is widely naturalised in Yorkshire, and I include a photo below in case it helps others get to grips with this species. It is very variable, merging into the parent species at the extreme ends of variation, but this example is pretty representative. Note the relatively matt mid-green leaves and the relatively large and broad leaf shape, which help distinguish it from our more attractive native Holly (Ilex aquifolium).

There was also a small tree of Cherry Plum (Prunus cerasifera) struggling to grow in the dim light of the woodland.

A small area at the northern end had clearly been the targeted by some misguided soul who felt it necessary to introduce garden plants into native woodland. The plants present included Hybrid Snowdrop (Galanthus x valentinei nothosubsp. valentinei) - of which more later in this post - and some well established clumps of Spring Starflower (Tristagma (Ipheion to the gardeners) uniflorum). The latter was not in flower yet and all that was present was these grassy tufts of garlic scented foliage (see below).

In contrast, the Eastern Sowbread (Cyclamen coum) was not very happy (the soil is a bit wet for this species) and is unlikely to persist.

Finally, my walk back took me past Swillington Park where a hedgebank supported a thriving colony of Hybrid Snowdrop. Again, this seems to be the cultivar 'Magnet', which, given it was first found in 1888, has had nearly 130 years to achieve a wide distribution.

Saturday, 27 February 2016

Double Daffodils

The double-flowered Wild Daffodil Narcissus pseudonarcissus f. pleniflorus ('Telamonius Plenus' aka '(Double) Van Sion' if you prefer) is just coming into flower in Oulton churchyard (VC63). It probably won't be in peak bloom for a few more weeks yet, so plenty of time to try and expand its known distribution. I have several records for VC64 but only one record for VC31 (Hamerton churchyard).

Two photos from the abandoned garden of a derelict cottage near Misson (VC56) in 2015

This odd daffodil did not appeal to me when I first saw it, but I find it growing on me in its intriguing and understated way, even if it is no good for the early flying bees. It is one of the oldest selected forms of daffodil in cultivation having arisen (or at least coming into circulation in England) in the 1620's. The relationship to Wild Daffodil is widely quoted but not always obvious in the flower colouration, it would be interesting to know if there is any molecular evidence that conclusively proves the relationship to this species. It certainly merits recording even if the parentage is not known with 100% confidence.

It is reputed to be highly variable in flower form,being strongly influenced by the environment and also with potential to vary from year to year. All the forms I have found, including those I revisit annually, seem reasonably consistent with a well defined perianth whorl and an amazingly convoluted corona, although as can be seen in the following photo the corona does sometimes burst at the seams (perhaps as the flower matures). Given the age of the cultivar, perhaps there is more than one strain in circulation and perhaps some are more consistent than others. Certainly there is evidence of this in the historic literature, and it might be better to treat it as a cultivar group rather than a single cultivar. In 1907 A.M. Kirby wrote in Daffodils, Narcissus and How to Grow Them 'Years ago when there was less demand for Double Van Sion, the growers of flowering bulbs propagated and disseminated their own types of ‘pedigree’ strains, and there was much rivalry among the growers as to the merits of their respective stocks, some having ‘rogued’ to the unburst double trumpet type, others to the ‘rose double’ form, i.e. trumpet burst, its petals curving backwards and intermingling with the perianth segments. Between these two extremes were several intermediate forms.' There is also evidence that it exists in diploid and tetraploid strains, which may add to the variation.

Oulton churchyard

It seems to be confused in certain corners of the internet with the (perhaps justifiably) rare double-flowered form of Tenby Daffodil (Narcissus obvallaris 'Thomas Virescent' (Derwydd Daffodil)) which is sketched and described in BSBI Welsh Bulletin 56. This strikes me as a very ugly daffodil, of which the Pacific Bulb Society photo seems credible (based on the description in the Bulletin) and reminiscent of the 'bunches of green bananas' description, and nothing like the various photos floating around elsewhere on the internet that look much closer to the far more appealing f. pleniflorus.

Thursday, 25 February 2016

Sunshine and Snowdrops

There is nothing better for the February doldrums than a day off work, sunshine and snowdrops. My local snowdrop hotspot is Oulton churchyard (VC63) and rather unexpectedly the edge of the Toby Carvery car park - I suspect the latter was once part of the grounds of a large house or old estate.

Toby Carvery

Oulton Churchyard, mixed forms of Common Snowdrop

The churchyard supports extensive stands of long naturalised snowdrops.Five taxa were putting on a good show today, but it really needed a little more warmth from the sun to get the flowers opening up a little more. Based on my experience gradually getting to grips with the genus, the most important thing is to temporarily ignore the flowers and your pre-expectations (they are not all Common Snowdrop (Galanthus nivalis)). What colour are the leaves (bright shiny green or glaucous)?, how wide are the leaves (same or less than the width of your little finger, or are some wider)?, and what is going on at the base of the leaves where they meet (this is the really important bit with the horrid terminology) - is the vernation supervolute (leaves overlap, see photo), applanate (leaves abut, like hands held in prayer) or explicative (leaf margin distinctly folded over towards the leaf undersurface)? Once all that is sussed, the flowers can be admired and scrutinised!

Supervolute vernation of the leaf bases, note the overlap

Common Snowdrop is abundant in the churchyard, and is present in two forms. Plants with single-flowers are f. nivalis and plants with double-flowers are f. pleniflorus (below). The cultivar of the latter is normally 'Flore Pleno' but there are other rare double forms best left to the Galanthophiles.

Galanthus nivalis f. pleniflorus

Equally abundant, and in fact a very common and frequently misidentified or overlooked snowdrop, is Galanthus x valentinei, a hybrid of Common Snowdrop and Pleated Snowdrop (Galanthus plicatus). It is common in churchyards, in some cases it may have arisen in situ but in most cases this is probably a naive assumption, as it is just as likely to have been planted in the past as the parents. This species typically has a good dose of hybrid vigour, and gets bigger still after flowering has peaked. Any particularly robust snowdrop is likely to be this species. It frequently (but not always) has the applanate vernation of Common Snowdrop, but the wider leaves (greater than your little finger) of Pleated Snowdrop. The photo below is of nothosubsp. valentinei, which only has a short apical mark on the inner tepals (as per Common Snowdrop). There are lots of cultivars and probably as many unnamed forms and self-sown segregates, so again in many cases it is best left to the Galanthophile to debate these. But in this instance I feel safe in saying almost all the plants in the churchyard are 'Magnet' or very close to it, given the shape of the apical mark and the nodding flowers on long pedicels.

Galanthus x valentinei nothosubsp. valentinei

The final two species are much rarer in the churchyard. Greater Snowdrop (Galanthus elwesii) has supervolute venation (as can be seen in the photo) and variably glaucous/glaucescent leaves. In this case the inner tepals only have a short apical green mark denoting it as var. monostictus.

Galanthus elwesii, note the leaves are glaucescent and some of the colour has been lost in the photo

In contrast to all of the above, Green Snowdrop (Galanthus woronowii) is unusual in that it has bright shiny light to mid-green leaves. It also has supervolute vernation. The form here was particularly robust (much better than my garden plant) with atypically large flowers (but within the published range of variation).

Galanthus woronowii