Tuesday, 13 August 2019

Hunting Aliens

If there's one aspect of biological surveying that I actively enjoy, it's getting in a car and square-bashing on a grand scale. Today's assault of the squares was devoted to the genus Crocosmia and was entirely inspired by Stephen Bungard's latest blogpost.

Montbretia (Crocosmia x crocosmiiflora) is a widespread plant up here, well-naturalised across many suitable areas. At this time of year great clumps of the stuff can be seen gleaming pale orange in roadside verges and near habitation, where it has usually managed to escape from a garden or two. A couple of years back, a visiting BSBI county recorder informed me that not all Montbretia up here is the hybrid, some of it is one of the parent plants, Potts' Montbretia (Crocosmia pottsii). He had one of the latter in his grasp and explained the differences. Obviously something stuck because to this day I keep an eye out for Potts' amongst the hybrid. Clearly, it is by far the less common of the two (hybrid swarms do kinda tend to...well, swarm) but there are a couple of clumps of Potts' Montbretia close to where I live, so I can keep my eye tuned in to the differences. 

Anyhow, today I decided to square-bash the entire north end of Skye in an attempt to discover which monads hold what montbretias. I took the coast road clockwise around the entire Trotternish peninsular but decided to forgo the Quiraing road; firstly because it's pretty inhospitable moorland and unlikely to be populated by any Montbretia, and secondly because I just couldn't stomach enduring the campervan mayhem that is The Quiraing in August. 

This is the BSBI map for Montbretia (Crocosmia x crocosmiiflora) on The Trotternish (data as of yesterday)

Dark red squares are recent (2010 onwards) records
As you can see, it's a fairly common plant up here. The interior of the Trotternish is mostly high moorland or mountains, with no roads going east to west (apart from the Quiraing road) hence inhospitable to Crocosmia in general. 

And here's the dots where I found Montbretia today. Some are duplications of those already recorded on the BSBI map, but others are new (or at least I hope they are). I deliberately ignored all Montbretia that were growing in gardens or immediately adjacent to gardens, only naturalised plants were counted. Admittedly, some of these may have been planted at some stage in the past, or more likely chucked out as garden waste but, by and large, Montbretia is a well-established plant across much of Skye and is probably only going to become more common in the future.

Dots are all at monad level (1km square)
I also found a few clumps of Potts' Montbretia (Crocosmia pottsii) in the general vicinity of habitation, often close to gardens. However, bucking that trend are the roadside verges at Staffin which are full of properly naturalised plants spreading along maybe a two mile stretch of the A855. Clearly it isn't anywhere near as widespread as Montbretia (yet!) but it is holding its own decidedly well in the grassy verges at Staffin. 

Here is yesterday's BSBI map for Potts' Montbretia in The Trotternish

The two upper squares are my records
And here's the map of today's sightings of Potts' Montbretia

Dots are all at monad level (1km square)
To my mind, there's a bit of urgency regards getting this genus mapped. Whilst flowering they are relatively simple to tell apart from one another (and to spot from a moving car!) But in another month or so these plants will lose their flowers and return into obscurity, yet more greenery in a sea of green. So we really at the last chance saloon for recording Crocosmia on Skye if we want to get it into the forthcoming Atlas 2020. Should there be a future national plant atlas, and I hope there will be, it probably won't be until about 2050. By then I suspect drones and DNA sniffers will be doing almost all of the fieldwork, plus I'll be an old fart, if not dead already, by then. Hence I need to make the most of this Atlas 2020 square-bashing project while I can. Pity I've come to it so late. Anyway, that's several more dots on the map for pottsii.   

There is just one other Crocosmia that has been recorded from Skye, one I've only ever seen growing planted in gardens. This is Aunt-Eliza (Crocosmia paniculata), which is the second parent of Montbretia (Potts' Montbretia being the other parent plant). Today, I spotted a few gardens that had Aunt-Eliza growing as feature plants either in large pots or in flowerbeds, maybe a dozen gardens in all. But then, as I was driving along the minor road through Achachork, I did a double-take, hit the brakes and backed up a bit. Fuckaduck - a great big healthy patch of Aunt-Eliza growing maybe fifteen feet back into an overgrown verge! Hell yeah, that's a lifer for me and a damn decent find too!  

Ok, it's a crap image. But you get the general idea! 
I thwacked my way closer to the plants and took a few more pics, before ripping up one whole plant to take back and key through properly. Despite looking as though this is the middle of nowhere, there are several big houses with well maintained gardens just the other side of this narrow road. Within another few hundred feet I'd spotted Montbretia and Potts' Montbretia in the verge and in gardens, plus several clumps of Aunt-Eliza a few hundred metres further up the road (in a garden). Almost certainly, this verge clump would have been dumped as garden waste at some point in the past, although I couldn't immediately see any other obvious garden plants in the ditch. However, it seems unlikely that somebody would have deliberately planted it outside of a garden, and in such an extensive stand, without introducing other species and then tending to them afterwards. It appears to be spreading by itself, vegetatively I presume. 

Huge, wide, heavily ribbed and pleated leaf blades

You can see which parent plant Montbretia gets it's zigzagging flowering stem from!
Oh! Note the stamens slightly protruding from the corolla mouth. That's not right...
I now find myself in a bit of a quandary. The material I took home with me appears to differ slightly from the material in the last two images. Right at this very moment, I feel I may need to change my initial identification. Purely from looking at these two images, despite checking what I physically have on my desk in front of me. How so, I hear you ask? Well...

I used Stace 4 and Poland to key through my specimen. Poland doesn't go by flower characters, Stace does. Between them I thought I had this nailed as Aunt-Eliza. Here's a pic of the plant I brought back



Using Stace 4 (features of the flower)
  • Perianth-lobes c 1/2 as long as tube or less, erecto-patent; stamens shorter than perianth > paniculata
  • Perianth-lobes c. as long as tube, widely spreading; stamens slightly exceeding perianth > masoniorum


Clearly, going by the flower in the above image, the perianth is a lot shorter than the tube, it's laying over on its side and there's no sign of any projecting stamens > paniculata (Aunt-Eliza)

BUT...

looking at the images I took in the field, some of the lobes look to be quite long in comparison with the tube, and some of the perianths are spreading. And I can definitely see stamens poking from the end of the perianth too. But not all. So it somewhat fits Aunt-Eliza, but not perfectly. 

Well guess what, there are other options. There's a thing called Giant Montbretia (Crocosmia masoniorum) which I had never heard of before this evening. Intriguingly, it has been recorded from several parts of the adjacent mainland. So is that what I have? Well, Stace's key would suggest so. But Poland has this to say regards the actual leaf blades themselves - tough > paniculata. Tender > masoniorum. Well, I have to say it's a comparative thing, and I have nothing to compare it with, making it a somewhat tricky thing to decide for sure. But after quite a bit of pulling, twisting and yanking, the leaf blade stayed intact, so I'll have to go with 'tough' over 'tender'. Which puts me back at an Aunt-Eliza that isn't quite right. 

Luckily (perhaps), the final option is one put forward by Stace himself. "C.paniculata x pottsii is probably the identity of most plants of so-called C.paniculata grown in gardens, and therefore of those naturalised". Which was the exact point that Stephen Bungard queried with me several hours ago. He's good that fella.

So it seems that I may have been a bit rash in claiming Aunt-Eliza, it may be a hybrid Aunt-Eliza. An Aunt-Potts' in fact. Well whatever it is, it will still be there tomorrow. And the next day. But I do need to get back to it before it stops flowering. Stephen will want a definitive answer one way or the other. As do I.

Best not get me started on the agrimony I spotted whilst square-bashing, it seems a bit kind of inbetweeny too. Must be something in the water up here.

Lowest spines spreading horizontally or ascending (ie not reflexed) > Agrimonia eupatoria

Some of the petals are definitely notched > Agrimonia procera


2 comments:

  1. It's even more complicated than you thought, Seth! C. aurea is the 'other parent' and there is also C. masoniorum to take into account - it seems quite plentiful in VC105.

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    1. Hiya Steve, yes you're absolutely right. I've just been forwarded an email correspondence between Stephen and a national expert regards Crocosmia identities. It's starting to look like a right can of worms I've opened, as you say it's more complicated than I thought. Much more complicated. Ho hum, we learn from the holes we dig ourselves, hopefully. Some nice fungi seen on Raasay today, the Kinloch and Armadale walks should be excellent!

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