Tuesday, 1 February 2011

New Mersey Valley Plant Finds 2010 - Part 2

Well, it’s the first day of February and in another few weeks spring will be here again and who knows what vegetable wonders and marvels I’ll find this year? Will it be a bumper year, like last year, or have I spotted all of the available wonders and marvels now? Somehow I doubt it.

Anyway, here are three more special finds from last year. This time I’ve chosen three introduced plants – what we botanists call ‘aliens’.
Although I would never, ever, advocate the deliberate introduction of plants into the wild I find it fascinating that some alien plants escape from cultivation and seek to establish themselves in the British countryside. A few of these aliens succeed only too well and become invasive, others are relatively well behaved and may actually add to our biodiversity, whilst a few just about hang on and remain as rare as ‘hen’s teeth’.

New Zealand Bitter-cress (Cardamine corymbosa) (Top photograph)

I live on Brookburn Road and at the bottom of this road is a pub called ‘The Bowling Green’. In front of the pub is a small paved area with wooden tables. This area is separated from the pavement by a brick-built, raised flower bed which is about waist high. One day last April I was walking down the road towards the pub and spotted, at the base of the raised flower bed, some tiny but brilliant white flowers. So vivid were these flowers that I actually spotted them from several yards away. As an inveterate weed spotter my heart began to race as I knew that this was something new!

These plants really were tiny – a maximum of a single brick-course high. Looking closer I saw that each flower had four petals and already there were long, semi-cylindrical fruits (i.e. seed pods) present. These features strongly suggested that this was a species of ‘crucifer’ and thus a member of the Cabbage family (Brassicaceae – formerly Crucifereae). But what genus and species was it? I confess that first I thought that it might be a species of Scurvy-grass (Cochlearia) – but that was a rather stupid guess because the leaves were completely wrong. Examining the bronzey coloured leaves I realised that they consisted of a few pairs of opposite leaflets and a single, larger, terminal leaflet. This is typical of the Bitter-cresses (Cardamine). Several native plants such as Lady’s Smock (C. pratensis), Large Bitter-cress (C. amara), Hairy Bitter-cress (C. hirsuta) and Wavy Bitter-cress (C. flexuosa) belong to this genus.

To determine the species there was nothing else for it but to key it out in Professor Clive Stace’s magisterial (but scary) ‘New Flora of the British Isles’ (3rd Edition, Cambridge University Press, 2010). After much swearing I decided that my plants were New Zealand Bitter-cress (which is really native to ... yes, you guessed it!). Stace tells us that it is: “Intr[oduce]d-nat[uralise]d but only in gardens; spread as horticultural contaminant to paths, rockeries and pavement cracks; scattered in Br[itain], Ir[eland] and [Isle of] Man, first recorded 1985”. So my specimens probably came from the flower bed above (and originally from a garden centre). I’m not sure, but my record could be the first Manchester record.

Salsify (Tragopogon porrifolius) (Middle photograph)

Last June FoCM Committee member, Julian Robinson led a guided walk around Sale Water Park. The focus of the walk was bird watching but here I have to confess that I’m a totally useless bird watcher. Someone spots a small, feathery dot in the distance and I point my binoculars in what I’m convinced is the right direction. Everyone else is ‘oohing and ahhing’ and commenting on the finer points of the feathery dot’s plumage ... and all I can see is a tree branch! By the time I’ve pointed the binos in the right direction the feathery dot has decided to fly away and to leave my newly acquired field of view!

After about half an hour of this I was skulking along at the back muttering balefully to myself (“Flipping birds! Why can’t they stay still and stop flapping about?”). By this time I must have reverted to my usual habit of scanning the ground because I suddenly stopped dead! There by the path was a plant around 500 cm tall and with purple, dandelion-like flowers. I knew instantly that it was a plant called Salsify (Tragopogon porrifolius). This species originates from the Mediterranean region and has been cultivated in the past (and may still be cultivated) for its roots – which can be eaten as a vegetable.

I had never seen Salsify in the wild, in Britain, before – but about 20 years ago I did find one of its close relatives when I was on holiday in Macedonia.

By the time that I’d checked the identity of the plant in the book and photographed it the rest of the party had disappeared and no-one else saw it.

Everyone else thoroughly enjoyed Julian’s walk but I suspect that they were all more adept at using binoculars than I am!

If anyone grows Salsify as a root vegetable I would be interested to hear about it.

Sowbread (Cyclamen hederifolium) (Bottom photograph)

The species Cyclamen hederifolium has a wide Mediterranean distribution and is found from south-east France to south Turkey, including many Mediterranean islands but excluding Cyprus (‘The Genus Cyclamen’ by Christopher Grey-Wilson, Timber Press, 1988). According to Prof. Stace it has been introduced and naturalised in Britain and was first recorded from the wild, in East Kent, in 1778 (Stace, 2010). This is long enough for it to acquire the common name, ‘Sowbread’. It is also probably the most common species in cultivation and is often grown in gardens.

On the 8th March last year (I’m being very specific about the date for a reason) I walked along the north bank of the river from Chorlton to Fletcher Moss. Around the West Didsbury area I found about 20 or 30 Cyclamen leaves spilling down the upper flood-bank. I suspected that the species was probably C. hederifolium but needed to see the flowers to be sure. I had to be patient because the flowers don’t appear until September; as it happens I found the flowers, in the same spot, on the 8th September – exactly 6 months after I found the leaves.

I still can’t decide if the plants were deliberately planted in that spot, or the corms deposited there in some flood, or they were self-seeded from someone’s garden (this species certainly seeds itself around in my garden).

As it turned out there were also some plants closer to home. At the bottom of Brookburn Road there’s a lane which leads to Hardy Farm and the path to Jackson’s Boat. The lane is gated at the Brookburn Road end and just by the gate is a spot where some people dump garden waste. This year a Cyclamen corm flowered on this dump. This plant was also C. hederifolium but a variety with white flowers (forma album). This was almost certainly a garden throw-out.

Dave Bishop, February 2011

No comments: