Saturday, September 3, 2011

Mud, mud, glories in mud

Thursday was wall to wall sunshine with clear blue skies and was most assuredly the perfect day for me to revisit RSPB Fen Drayton. And the sunshine was very important for this visit.
(The photo above was actually taken on a cooler, cloudier day a few weeks back.)
My first stop was close to the car-park. Sticky groundsel grows prolifically in the gravelly area just through the kissing gate. Senecio viscosus, to give it its scientific name, literally means, sticky old man. The seed heads are white and fluffy like a mop of white hair. The yellow flowers are drop dead gorgeous and worth a pause for full appreciation. 
A UV picture of the flowers is here (I have to disagree with the comment underneath the UV photo on this site as I think this is a beautiful flower). Sticky groundsel is a plant of freely-drained areas, including coastal shingle. It's a neophyte (a plant which arrived in the UK after 1500), first recorded in the UK 1660, and now expanding its range (although maritime plants may be native).

The plant is covered with sticky glandular hairs, which give it its greeny-grey look. I love the way the petals (ray florets) curl back as the flowerhead finishes. And it is deliciously sticky.

After getting my fill of sticky groundsel (it took a good few minutes), I ventured off in search of a very special plant. On the way I passed water mint (Mentha aquatica), giving itself away, before I even saw the lilac flowers, by the wonderful aromatic scent wafting up to stimulate my olfactory organs as my feet crushed its leaves. 
And I always enjoy seeing gypsywort (Lycopus europaeus).
Finally, I came to the spot I'd been directed to. My quarry was a small (about 10cm tall) plant which frequents ephemeral pools and muddy scrapes. Callaghan (1958) describes it as a 'scarce annual of disturbed ground dependent on winter flooding'. Let me introduce the wonderful grass poly (Lythrum hyssopifolium (although see my comment at the end of this post regarding its botanical name)). 
OK. That doesn't look too exciting really does it? Especially being over-exposed like that. But it is. It really is. Grass poly is a specialised little plant with very particular habitat requirements. It likes mud; flooded in winter, dried out in spring. And it's so easy to overlook, looking to all intents and purposes like a knotgrass. Until you get down on your knees (in those muddy wet hollows it so favours) to look at its delicate pink flowers, which only open in sunshine. One has to throw dignity to the wind to get photos of these plants. So bottoms up then...
Grass poly is rare. It is protected under Schedule 8 of the Wildlife & Countryside Act 1981 and listed in the UK Red Data Book. It occurs on few sites in the UK now; here at Fen Drayton, on agricultural land near Fowlmere in Cambridgeshire, Slimbridge reserve in Gloucestershire (where it is very numerous) and most notably a newly discovered site in Kent at Fowlmead Country Park. It seems to have found a stronghold in scrapes on wildfowl reserves, now it's almost banished from agricultural land due to large scale land drainage.  
Yay! Glorious!
Grass poly is also called hyssop loosestrife after its supposed resemblance to hyssop (Hyssopus officinalis), an aromatic herb with small blue flowers. They are not actually related. The following picture of hyssop was taken by Armin Jagel at Ruhr University Botanic Garden. It is used here from Wikipedia under a Creative Commons Attribution-Share Alike 3.0 Unported license.
When you look carefully at grass poly, its kinship with purple loosestrife (Lythrum salicaria) is plain to see. Purple loosestrife is tall and showy, but the flowers and fruits are similar to its smaller, rarer relative. This lush purple loosestrife is growing in my garden pond.
I was still on a high from seeing the poly so omitted to check the identification of this water speedwell (Veronica spp.). Pink or blue? I know not. 
And I believe the plant below is trifid burr marigold (Bidens tripartita). The leaves are serrated and the flowers lack ray florets (in this case), although most of the plants I saw were heavily grazed and the flowers were spent. Again I must claim poly-over-excitement as the reason for my sloppiness. Well, it's a Bidens anyway!
While at Fen Drayton I also wanted to return to see the parasitic greater dodder (Cuscuta europaea) on the River Great Ouse (blogged here). 
The dodder was well past its best, being mostly brown and shrivelled. A few bits were looking less autumnal though.
I tried to get close-ups of dodder's haustoria (the bits that penetrate the nettle stem which the dodder parasitizes) but can't quite (understatement alert) rival Phil's pictures on A Digital Botanic Garden.
A kingfisher flitted past and the swans were splashing about in the river. 
Lovely birds.
There were clouds of bat grub.
Fen Drayton was really beautiful in the sunshine. I looked for a black tern I'd been told might be flying over the site, but it was a no show. 
On the edge of the lake, last time I visited, I found a leech in the shallows. 
I've no idea what species, but it looked quite listless.
No leeches on this visit, but I did rescue a forest bug (Pentatoma rufipes) from the water. It got a bit sandy at first...
...but soon dried off.  
I put it in some vegetation nearby and wished it well.

I sat back to enjoy the vista. There was little to mar the peaceful lakeside atmosphere until some dogs charged into the water. Hmmm. Dogs can't read, but people can.

My complaints to the owners elicited the response that, 'There's enough room for all of us here'. Well, no there isn't. Fen Drayton is a nature reserve. And we have nature reserves like this because clearly (to me at least) there is not enough room for all of us and for the special birds who live here. Nature reserves are reserved for nature. For the birds. Not for dogs. 

Lythrum hyssopifolia or Lythrum hyssopifolium?
It seems there is some confusion in the literature re. the correct scientific name of this plant. Some say hyssopifolia, some say hyssopifolium. Confusingly the US Department of Agriculture, on one website calls it L. hyssopifolium L. and on another website calls it L. hyssopifolia L. Hmmm. OK. If we go back to the original Linnaean text of the Species Plantarum, Volume 1, page 447, the correct name appears to be Lythrum hyssopifolia L.. But, and I am not a Latin scholar, Lythrum the generic name, has a neuter ending 'um' so, perhaps the specific name should also be neuter? So is hyssopifolium grammatically correct? Maybe not. In this short discussion from 1998, much of which goes over my head, some grammatical mysteries called 'nouns in apposition' are mentioned (I missed that day at school) and 'neither can be altered to agree in gender with the noun (Lythrum) they modify'. I retire here, as I am way out of my depth! 

Bibliography & Further Information
Callaghan DA (1958) Biological Flora of the British Isles: Lythrum hyssopifolium L. Journal of Ecology, Volume 58, Issue 6, Pages 1065-72.
Callaghan, DA (1996) The conservation status of Lythrum hyssopifolia L. in the British Isles. Watsonia, Volume 21, Pages 197-86
Here's more info on Fen Drayton from the Cambridge Bird Club.
I was inspired to go to seek out this little plant by blogger Kingsdowner in Kent. I had exact directions of where to find the plant, he however achieved the Herculean task of tracking it down in Fowlmead Country Park, only knowing that it occurred somewhere on the site. Chapeau.


  1. Hi Mel, when I used to mist net at Dungeness, the trapping area used to hold a great patch of Sticky Groundsel. A day spent tramping around the net sites meant a sticky coating on my trouser legs. Not pleasant at all...

  2. Glad you found them - presumably with some assistance as it's a big place. Great photos of the little plant, clinching the ID.
    May I point out that the search was renewed for the Fowlmead grass-poly after your inspriation.

    Please send some Greater Dodder seeds to Kent, as it became extinct here in 1864!

  3. Steve, so sorry to hear about your unpleasant close encounter with SG.
    KD - Yes, I was given pretty good location details by one who knows. Still took a while to get my eye in though. Am glad to have inspired a search for poly in Kent. Fowlmead is fascinating because of its history of disturbance and the ongoing disturbance. It deserves some botanical attention.
    And I'd be delighted to send greater dodder seeds to Kent. We have lost so much of the diversity of our wild flora, so why not re-introduce it? It's a flipping fantastic plant.

  4. lythrum hyssopifolia is a weed in southern part of Australia and there are quite a bit in my area. They are cute when in flower ( many months, lovely as Vervain officinalis flowers) and I for one picked a few and transplanted in my garden where it floods in winter.