Thursday, September 22, 2011

In the mud.......again

Monday was a lovely sunny September day and perfect for a return visit to RSPB Fen Drayton to see a special little plant. A little plant worthy of another post.

After my previous post on grass poly (Lythrum hyssopifolia), Roger Cope (Beeston Wildlife Group) emailed me to ask if he could come and see it. The RSPB warden Jacqui Miller was duly contacted and she agreed to meet us on Monday afternoon. I even managed to drive there without getting lost en route this time, thanks to having someone in the car to read the map.

For starters, before we'd even met Jacqui, we were both pleased to see annual mercury (Mercuralis annua) growing by the gate in the carpark. Annual mercury is usually dioecious so has male and female flowers on separate plants. How apt that they are growing by a kissing gate.

Jacqui met us and took us to the place where the protected species grass poly grows. It's a small, easily missed plant and incredibly rare so a real privilege to see it again. I was surprised and delighted that it was still in flower. It was growing new shoots from the base too. 
The seed capsules were forming. Each capsule contains about 25 seeds (see 1968 paper by Edward Salisbury here).
Grass poly survives in pretty harsh conditions; damp, muddy hollows in arable fields (see abstract here). Its seeds germinate in the spring after winter flooding (the flooding reducing competition from other species). Poly seems to be very sensitive to competition.

It's just lovely.

After saying good bye and thank you to Jacqui, Roger and I headed up to the River Great Ouse to see greater dodder. 
On the way we passed ossier (Salix viminalis), basket willow growing on the river bank. Its leaves are long and thin with smooth edges. The word 'osier' is from the French meaning withy or basket willow. Auseria is medieval Latin for willow bed.
The showy flowers of hedge bindweed (Calystegia sepium) brightened up an increasingly cloudy day. 
I now know the way to remember the difference between hedge bindweed and great bindweed (Calystegia silvatica). C.sepium has its sepals showing and not covered by the bracts. In C.silvatica the sepals are covered by the inflated large bracts. Sepium = sepals showing. Easy peasy. Got it! Here is a close up of those uncovered sepals, making this C.sepium.
On the riverbank we were both delighted to find the parasitic greater dodder (Cuscuta europaea) still in flower (first blogged on 8th August 2011). Here it is scrambling over its nettle host.
Lovely, lovely little flowers.
I managed to find some dodder attempting to parasitize itself, but am reliably informed that the haustoria cannot penetrate dodder's own stems. See Phil's post on dodder at A Digital Botanic Garden. 
As we walked alongside the new busway back to the car, 2 things happened which made us stop and stare. First, a bus zoomed past with the driver waving both his arms at us and smiling in a 'look I can drive with no hands' sort of manner. Disconcerting behaviour for a public bus driver until you realise the busway is guided and the driver is actually meant to be hands-free. (See addenda below.)

And second, this mullein caught our attention. It didn't look like great mullein (Verbascum thapsus). So down went bags, out came books and floral keys were consulted.

The plant was shorter than great mullein but still very hairy although not as woolly. The stem was ridged. 
The flowers were large and showy. We thought it might be orange mullein (Verbascum phlomoides).....
.....but, I took this photo (below) of what I think is orange mullein in a neighbour's garden yesterday. Orange mullein is a garden variety and a frequent escapee into the wild. Love those woolly stamens. 
So we came to no firm conclusion on id. Any help gratefully received.

Some hops (Humulus lupulus) were scrambling about by the track.

The etymology of Humulus is unclear but may be linked to humus or rich soil. Lupulus is from the Latin lupus, a wolf. Mrs Grieve cites Pliny as describing how hops were grown amongst osiers (ahha!!) and they strangled the willow wands as a wolf might strangle a sheep. Do wolves strangle sheep? The word hop is from the Anglo Saxon word hoppan which means to climb.
The cone-like female flowers are called strobiles; the parts of the plant used to make beer taste bitter. I think they smell lovely. When I opened these pictures of hops to edit for the blog, I could actually smell hops for a few seconds. Weird sensation :-)
Another enjoyable day at Fen Drayton and great to share with a fellow botanist.

I make no apology for blogging about dodder or grass poly over and over and over again. Both are simply amazing plants.

If you are not a member of the RSPB (and why not?) then I'd encourage you to join here.
Update: There are 3 upcoming events at Fen Drayton;

30th September: Autumn Birds
5th October: Stars at Night
8th october: Fungus Foray

Addenda
The guided busway between Cambridge, St Ives and Huntingdon opened on 7th August 2011. I just happened to be visiting the reserve that day. Here is the busway looking towards Cambridge.

And a bus on the way to St Ives.
Fen Drayton RSPB reserve now has its own bus stop
Busway information re. timetables and fares is here. The buses are flash. They have leather seats and air con (OK, so has my car) + free wifi and plug sockets (not got that though). 

8 comments:

  1. Hi Mel, Fascinaing post. Looking at your pics, I'm beginning to wonder whether it is true that dodder haustoria can't penetrate their own stems. It's one of those oft-repeated 'facts' that I've always assumed to be correct, but having never checked first-hand, I'm beginning to wonder....

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  2. Hi
    Enjoy reading your blog. I initially thought the verbascum was v. nigrum but I'm not sure. The unknown fungi on a previos post looks like Boletus porosporus (Sepia bolete). Thanks for visiting my blog...I wish I could see some of the plants you see down there!

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  3. Hi Phil
    Good to hear from you. I've not done any research on self-parasitizing dodder - but just picked this up on Google
    http://www.pakbs.org/pjbot/PDFs/43(4)/PJB43(4)1853.pdf
    Not read it yet. Will do so later and see where it might lead. Interesting indeed. Mel

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  4. Hi Abbey Meadows. Love your blog!
    Yes, Roger and I struggled with the Verbascum. Meh. Perhaps we were poly'd and dodder'd out.
    We considered nigrum too but the white hairs on the stamens?....The flowers were not stalked so that put me off phlomoides....and the stigma was not clearly spoon-shaped IMH0. Next year I'll get a handle on mulleins. Hey ho.
    Thanks for fungi id :-) Have a few more in an upcoming post from a walk round the RSPB that I'll need your help on too.
    Mel

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  5. Another erudite post, Mel. It's fascinating to know that we both have little enclaves of grass-poly nearby, and can share info to (hopefully)help manage the sites.
    Hi Phil and Nigel, fancy meeting you here!

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  6. Hi Steve
    I'm looking forward to seeing the Kentish poly next year. Agree about sharing info as GP sites so few now. Would also like to see the plants at Slimbridge.
    Also blogging about poly, as we have both done, reminds people these little plants exist - but are only just hanging on by a thread and may be lost if we don't do something.
    Mel
    Are you lads all having a meet-up on my blog?

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  7. Lovely plants to see again.

    Wolves bite and hold onto the throats of larger animals when they are attacking them.

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  8. Hi Pat
    So that fits with Pliny's 'strangling'.
    Thanks

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