The Draw of Drawdown

Mike Wilcox sent me interesting news this week that left with me with mixed feelings. He had popped over to Skelton Lake, part of my local patch, and found Mudwort (Limosella aquatica) - a cracking find and the first for the Aire Valley (at least in living memory if not all time). I was pleased because I had been expecting and hoping that this species would turn up, tempered by annoyance that if my weekend walk had taken a slightly different route then I would have got it first!

So naturally I went for a look this weekend and to take a few pictures. In so doing, I was able to extend it even further into the VC64 part of the lake.

Mudwort habitat

This really has been an exceptional year at this site, with water levels dropping consistently over the summer. In recent years rain in summer has re-filled the lake, putting an end to the drawdown season before it had fully got going. The Mudwort has joined the other recent cracking finds of Grass-poly (Lythrum hyssopifolium) and Golden Dock (Rumex maritimus).

A range of other species were putting on a good show. Including this really robust Persicaria. I really wanted this to be something different, it is so striking with its spotted robust stem, distinct nodes, multiple stems arising straight from the root stock and decumbent at the base, and sub-glabrous leaves. But I had to face facts, it was just a form of "Pink" Persicaria (Persicaria lapathifolium subsp. lapathifolium - in my view the circumscription of this in Flora Nordica seems more usable than the more recent one in Sell & Murrell, which under-describes the diversity of the two subspecies). Normally a plant this distinct and forming a distinct population would merit a name (of whatever rank), but the trouble with the Persicaria's is that they are autogamous, throwing up new variants which then breed true. Perhaps if its more widespread ... let me know if you've seen it elsewhere.

It was also nice to see the "Intermediate" Plantain (Plantago major subsp. intermedia), making its 2018 appearance on the strandline.

Unexpected, and again first seen by Mike, was this sunflower (Helianthus annuus).

All this, without mentioning the knotgrasses. That's a subject for another day, but as a taster, Polygonum microspermum. A delightfully dinky species with blue-tinged foliage and tiny flowers. Seems quite a reasonable split to me, especially when seen growing in the 100's.

VC64 End of Season Update

I have just finished crunching an excellent and large batch of records from Bruce Brown, who has been really active for the New Atlas in SE04, 05 and 06 over the summer. I'm looking forward to seeing what his efforts do for the stats on these hectads.

My personal choice of highlights include, starting with the natives:

The under-recorded reservoir drawdown specialist of 'Intermediate' Plantain (Plantago major subsp. intermedia) at Embsay and Grimwith Reservoirs. The latter also had Mudwort (Limosella aquatica), a very scarce species and one not recorded from that hectad recently. All photos mine unless otherwise stated.

 Plantago major subsp. intermedia

Limosella aquatica

Grimwith Reservoir also rewarded Bruce with two interesting hybrids, Shore Horsetail (Equisetum x litorale) and Myosotis x bollandica. There is a nice account of the latter with photographs here. Bruce also found the Myosotis on Crawshaw Moss, and the number of records of this hybrid in general are accruing with some regularity after its first description in 2012.

Bruce is well known locally for his interest in and knowledge of ferns. Finds this year include Oak Fern (Gymnocarpium dryopteris) and Beech Fern (Phegopteris connectilis) at Strid Wood. Neither fern is common in the VC,

Gymnocarpium dryopteris (photo by Griensteidl de Benutzer, Wikimedia Commons)

Phegopteris connectilis (photo by Griensteidl de Benutzer, Wikimedia Commons)

Other good finds include Small Teasel (Dipsacus pilosus) by the River Wharfe near Bolton Park, and Cloudberry (Rubus chamaemorus) at Thorpe Fell trig point.

Dipsacus pilosus

Moving onto non-natives. Bruce found the diminutive and probably much-overlooked Least Duckweed (Lemna minuta) in the pond at Embsay Nature Reserve. While at nearby Draughton he found Turkish Wood-spurge (Euphorbia amygdaloides subsp. robbiae). I have never understood why this is not afforded species status. Perhaps it will be one day so I am glad to have the record to subspecies level.

Euphorbia amygdaloides subsp. robbiae (photo by Dominicus Johannes Bergsma, Wikimedia Commons)

Another garden favourite occasionally found on road verges is Purple Crane's-bill (Geranium x magnificum), Bruce found this at both Embsay and Draughton.

Geranium x magnificum (photo by Meneerke bloem, Wikimedia Commons)

The Draw of Draw-down

Draw-down, the seasonal exposure of sediments around the margins of ponds, lakes and reservoirs over the summer, is a habitat I always like to explore whenever I have the opportunity. It is as appealing to me as arable field corners, as you never know what you might find, and there can be much of interest in late summer when other habitats are winding down.

I have been lucky enough to get around a fair few reservoirs in VC63, 64 and 65 in recent weeks and have found plenty of surprises and also, to be honest, a fair amount of not so much. Its the boring sites that make the other sites so much more rewarding. Here are a few of the highlights.

Mudwort (Limosella aquatica) at Scargill Reservoir courtesy of my colleague Hannah Mitchell, also present at Swinsty and Fewston Reservoirs

Musk (Mimulus moschatus) on the mudflats at the northern end of Fewston Reservoir

A rather poor photo that does not do justice to this delicate species - Small Water-pepper (Persicaria minor var. minor). The whole population at Swinsty and Fewston is the unusual white-flowered form. The more typical pink-flowered form was encountered later at Leighton Reservoir

Not as rare as the preceding species, but it is always nice to see Water-purslane (Lythrum portula subsp. portula). 

Intermediate Plantain (Plantago major subsp. intermedia), a drawdown specialist unlike its weedy cousin Greater Plantain (Plantago major subsp. major)

And that's just a taster without mentioning Shoreweed (Littorella uniflora), Sand Spurrey (Spergularia rubra), Marsh Speedwell (Veronica scutellata), Red Goosefoot (Chenopodium rubrum), Monkey-flower (Mimulus guttatus) ...

You've probably noticed the recurring theme in most photos by now - the menace that is New Zealand Pigmyweed (Crassula helmsii). Please take care to clean your boots so as not to help it spread any faster than it is already managing, otherwise you get this ....

Fewston Reservoir, that really is all New Zealand Pigmyweed and this is but one small part of the infested shoreline of this large reservoir

Golden Dock at St Aidan's

With sunshine and blue skies today I thought it worth a late season trip to St Aidan's (VC64) to see if any of the Golden Dock (Rumex maritimus) rosettes seen earlier in the year had made it to flowering. I was rewarded with four plants, one of which was in peak bloom and worth photographing. This species was more abundant a couple of years ago, water levels and goose trampling haven't favoured it recently. I also wonder if the recent rapid spread of New Zealand Pigmyweed (Crassula helmsii) is also impeding germination.

Golden Dock is a rare plant in VC64 and is largely restricted to a few wetlands in the far east of the county. It is a little more frequent in VC31, but it is still a scarce plant of drawdown habitats.

Less attractive, but equally pleasing - at least to me and perhaps because it requires a little more investment in time to go beyond a species-only identification - was the scattering of the wetland specialist subspecies of Greater Plantain (Plantago major ssp. intermedia) along the drawdown zone. While identifications should always be confirmed by counting the number of seeds in a pod (>15 seeds is diagnostic) it is very distinct once known, with its typically diminutive size, pointed leaf tip, toothed and hairy leaves, and usually decumbent inflorescence. It is also much more specialist in niche than its more competitive and weedy sister (ssp. major), normally being associated with disturbed damp ground, and often only germinating and flowering late in the season.

A final lucky find was a second location for Greater Soft-rush (Juncus pallidus), again doing its best to blend in with the Club-rushes (Schoenoplectus spp.). The following photo is pretty ropey (I should have got my camera out rather than using my phone), and it does nothing to show the size of the plant which was easily as tall as me.