Mad Dogs ...

 ... and botanists go out in the mid-day sun on the hottest day of the year so far. Crazy, but I'm not one for wasting sunshine (I live in Leeds after all), especially after a spring lost to covid and excessive rainfall. So, I took one of my lazy weekend routes out along the shade of the river corridor towards Mickletown (VC63) and then back via St Aidan's (VC64).

Over the winter the Canal and River Trust had cleared a path through the woodland on the river bank near Lemonroyd Marina (VC63). This new route gave me the first good find of the day - several bushes of the irredeemably pungent Stinking Tutsan (Hypericum hircinum subsp. majus). A new species for my home patch.

Further on was a bush of hazel yet to be stripped of its nuts by voracious grey squirrels. This is one of the hybrids between the native Hazel (Corylus avellana) and the Filbert (Corylus maxima). This form could be easily mistaken for the latter but the involucre is not fully closed over the nut and consequently the nut is visible. This would key*, given the nuts are obviously longer than wide, to the form Peter Sell distinguished as Corylus avellana f. schizochlamys. However, the length of the involucre and the pronounced pinching over the nut means it is not a good match. It looks to have much more of an influence from Corylus maxima than is typical for this form.

Further on, and handy for comparison purposes, I found another bush likely to be part of this hybrid spectrum. Its a common form with very large nuts that are about as long as wide. Under Peter Sell's classification it can be called Corylus avellana f. grandis. Again the involucre exceeds the nut, which is a trait potentially derived from Filbert.

Out in the sun near Mickletown (VC63) there was an impressive mixed stand of Broad-leaved Everlasting-pea (Lathyrus latifolius), a garden escape. The pale-flowered plants seems a good match for the cultivar 'Rosa Perle', while the darker ones seem to be 'Red Pearl'.

Next to the pea was a distinctive bramble. This being, Slender-spined Bramble (Rubus elegantispinosus), a species that I learnt under lockdown last year. Baby steps with this genus. I remain ever hopeful for a regional handbook with photos.

The final treat of the day was the swathes of Hare's-foot Clover (Trifolium arvense) lining the track through St Aidan's (VC64). This species has exploded in numbers in recent years and is always a welcome sight.

* Update: I would modify this to accords with the pictures in Sell & Murrell. The descriptions seem back to front with the pictures. While it would be tempting to rely on the descriptions, I am also swayed by the description of var. grandis (the "big round nut" as originally defined in its latin diagnosis) in this account (European Journal of Taxonomy 409(409):1–45). This also seems to indicate that f. schizochlamys is not correctly applied in Sell & Murrell. All this is possibly academic given the more you look, the more variation can be found. It seems likely that these named forms only represent a tiny proportion of the true variation of this long cultivated tree, and at best are only loose groupings. I am increasingly inclined to take the stance of Alan Leslie in his excellent Flora of Cambridgeshire.

Bottom Boat and Back

I made the most of the good weather on Tuesday to walkover over to Bottom Boat (VC63). Its not a route I do often, as it requires a bit of a slog up and over the ridge that separates the Aire Valley from the Calder Valley, but it does offer potential for interesting casuals and escapes and usually provides something of interest.

The day started well before I had even left Oulton with some particularly robust Cockspur (Echinochloa crusgalli) on an arable margin. This seems to have sprung from nowhere given I walk pass this field regularly.

Reaching my target destination I stumbled on a patch of derelict hardstanding with a variety of interesting garden throwouts. This is where I met 'Angelina' (see previous post). Other highlights included:

The golden form of Wilson's Honeysuckle (Lonicera nitida 'Baggesen's Gold').

Pink-sorrel (Oxalis articulata), in association with Stinking Hellebore (Helleborus foetidus) and surprisingly, as I did not know that it can throw up leaves in autumn, Garden Grape-hyacinth (Muscari armeniacum).

Stinking Tutsan (Hypericum hircinum).

Slightly further on, this attractive bi-coloured cultivar of Broad-leaved Everlasting-pea (Lathyrus latifolius 'Blushing Bride') was still going strong.

While an arable margin nearby had the winged form of Black-bindweed (Fallopia convolvulus var. subalatus). Supposedly less common than the nominate form, but that is not my experience.

Working my way down towards the River Calder I moved into abandoned former colliery land. Not the richest of habitats, it needs a few more decades yet, but still with interest and its great that no one has tried to 'restore' it. 

By the farm track on route was a young and apparently self-established tree of Cherry Crab (Malus x robusta), a variable group that perhaps includes plants of other origin. One of the characteristics of this species is that the individual apples are variable in terms of whether or not they retain their sepals. I think it likely that the fruit will colour further, they were in shade so a little behind.

Heather (Calluna vulgaris) is already starting to move in amongst the secondary birch woodland, a species that is very uncommon in the lowlands of Leeds and Wakefield.

But keeping with the theme of unusual non-natives there is also a thicket of sapling Broad-leaved Cockspurthorn (Crataegus persimilis 'Prunifolia'). No idea how that arrived, but it does not look planted. It proved the first of several interesting (at least to me) hawthorns.

Further on, the landscape architects had been in at some point in the last 30 years 'restoring' the landscape and creating 'native woodland'. Of course its nothing of the sort, rank MG1 grassland and the usual mix of false natives and lookalikes. Among these was a tree currently going by the name of Miyabe's Maple (Acer miyabei). The true species is of Japanese origin and, like Alan Leslie notes in Flora of Cambridgeshire, I think our plants are probably something else. The question is what? Potentially it is an unnamed alien form of Field Maple (Acer campestre), but possibly as with many planted 'native' hawthorns, dogwoods, Viburnums and hazels it could be of hybrid origin. Its a striking tree though, with large leaves, long petioles and large keys (glabrous in this case but they can be hairy). The second photo below contrasts it with typical field maple (var. campestre).

There was also Coralberry (Symphoricarpos orbiculatus) and  the hybrid hawthorn Crataegus x subsphaerica. The latter in this case had foliage closer to Common Hawthorn (Crataegus monogyna) but with clear hybrid vigour, but those elongate erect sepals give the game away.

One final hawthorn brightened the walk home. Check out the haws on this Common Hawthorn, c. 13mm long by nearly that wide. Living up to its name of var. splendens. These large fruited bushes occur here and there amongst more typical plants. I'm not quite sure what to make of them (valid variety or just chance?), but they make a stunning sight in the autumn sunshine. The bottom photograph compares it with more typically sized haws from a neighbouring bush.

Blink and You'll Miss It

Grass-vetchling (Lathyrus nissola) is one of those plants that is only visible for a few brief weeks each year, so its always a pleasure if you manage to find it in full bloom. Brian Davis sends news that he has just re-found it at Kimbolton Airfield, Huntingdonshire where it was last reported 10 years ago. I was also lucky enough to find a 100 or so plants along an arable margin at Old Weston, where the following photo was taken.

While enjoying the vetchling, something else caught my eye that I would otherwise have missed. An unusual vetch with a yellow tinge to the flowers (although not as yellow as some books suggest - it is quite a variable species and a pinkish tinge to the standard is not uncommon) and distinctively hairy seed pods. This turned out to be Yellow Vetch (Vicia lutea), new to Huntingdonshire.