This article was first published in the Newsletter of the London Natural History Society, No. 240 February 2016
Well, where did that year go? Here we were again meeting Nick Bertrand at Deptford Station, ready to embark on the annual quest for plants in flower on 1st December. In stark contrast to last year’s foray, we were accompanied by sunshine, which had been rare in the previous days. Once again, this was a year that broke previous records for various climatic variables. One thing is for sure, things are heating up encouraging certain species to forgo their winter break.
Eight of us set off with Nick up into the station to view the rough grassland that had previously got us off to a flying start in terms of species numbers. However, time passes and succession marches on; the resulting increase in scrub meant that we really did have to keep our eyes peeled. All 16 species were familiar faces of our urban environment. Among others present were Red Deadnettle Lamium purpureum, not so profligate with its flowering, Annual Mercury Mercurialis annua, Yarrow Achillea millefolium, Hawkweeed Oxtongue Picris hieraciodes, Perennial Wall-rocket Diplotaxis tenuifolia and another grass, but one more associated with the summer months, False Oat-grass Arrhenath-erum elatius. The most numerous species in that patch, five in all, were representatives of the Daisy family Asteraceae, again no surprise given it is our most common family.
Deptford High Street provided us with that fine adornment of walls, Ivy-leaved Toadflax Cymbalaria muralis, nearby were Hairy Bittercress Cardamine hirsuta with its four stamens and Shepherd’s Purse Capsella bursa-pastoris in one of its many guises. Although not the subject of our search, I couldn’t help but notice three small saplings defying the paving – Holm Oak Quercus ilex, Pedunculate oak Q. robur and our most urban of shrubs, Butterfly-bush Buddleja davidii.
We turned into Comet Street, a most unprepossessing back alley which, by that very nature, was a little treasure trove as we struggled in our search. Small-flowered Crane’s-bill Geranium pusillum was our first find, to be eclipsed by a plant which had Nick working through numerous corruptions of its Latin name before arriving at the mouthful that it is, Four-leaved Allseed Polycarpon tetraphyllum. This winter-annual formed a veritable carpet on a cobbled area and is a tiny plant altogether, never mind the flowers, but there they were. Whether native or alien is uncertain, but it has been present in the south-west since 1770 and has now made its way up to the Big Smoke popping up north and south of the river. Its companions were ‘regulars’, including Groundsel Senecio vulgaris, Petty and Sun Spurge Euphorbia peplus and E. helioscopia, and Black Horehound Ballota nigra. A regular, which Nick has never recorded in flower at this time of year, was Cleavers Galium aparine (trust Jill to spot it!).
A small green added another Geranium species, Hedgerow Crane’s-bill Geranium pyrenaicum, with Smooth Hawk’s-beard Crepis capillaris, Spotted Medick Medicago arabica and, guess what was on the corner of Speedwell Street? None other than Common Field-speedwell Veronica persica! At the corner of Comet and Watson’s Street, was a tall, none too impressive Privet hedge Ligustrum vulgare not, I hasten to add, in flower, but providing habitat for a colony of sparrows. Watson’s Street also provided us with two more Asteraceae, Nipplewort Lapsana communis and Feverfew Tanacetum parthenium, which the books assign to the July-September and July to August flowering slots respectively, hmmm.
As we proceeded each street furnished our list with a few flowers. In Arbuthnot Street was another wall-associated species Pellitory-of-the-Wall, Parietaria judaica along with Mexican Fleabane Erigeron karvinskianus, obviously enjoying the British winter. Broad-leaved Willowherb Epilobium montanum was another species which I really did think had retired for the season. In Amersham Vale there was London Rocket Sisymbrium irio, which shot to noticeability following the Great Fire of London, but now is a bit of a rarity (how hot does it have to get, I wonder?). Companions included Small Nettle Urtica urens, Black Medick Medicago lupulina and Bramble Rubus fruticosus.
Warwickshire Paths’ contribution included Pot Marigold Calendula officinalis, Purple Toadflax Linaria vulgaris and Sweet Alison Lobularia maritima, three species which, although they had much earlier introductions, were not recorded from the wild until the early half of the 17th century.
Our third Geranium of the day came in the form of Herb-Robert Geranium robertianum and as lunch beckoned Cockspur Echinochloa crus-galli and Narrow-leaved Ragwort Senecio inaequidens brought our total to 65.
After the Cafe Bianca, which refuelled us for the afternoon shift and left me with the thought ‘To thine own self be true’ (such is the nature of LNHS lunchtime conversations!), Nick and the bulk of the party took off, followed by two tardy souls. The result was two routes were taken, one taking in the grounds of St. Pauls Church, part of a Site of Importance for Nature Conservation. Despite this, intense tidiness ensured there was nothing to add to the list; the other route took in Crossfields Open Space, where Hoary Mustard Hirschfeldia incana and Common Ragwort Senecio jacobaea were noted.
Hairy Tare Vicia hirsuta and Perforate St. John’s-wort Hypericum perforatum were found in Sue Godfrey Nature Park, then we arrived at the Creekside Education Centre where numbers were boosted considerably, despite the distraction of the demolition of the warehouses on the adjacent site. A clutch of red flowers included Scarlet Pimpernel Anagallis arvensis, Red Valerian Centranthus ruber, Viper’s Bugloss Echium vulgare and Round-leaved Crane’s-bill Geranium rotundifolium, and the ‘whites’ included White Melilot Meliotus albus, Wavy Bittercress Cardamine flexuosa and Common Whitlowgrass Erophila verna, an early-flowering annual, but not this early!
On Ha’penny Hatch Bridge Nick showed us a very recent arrival to the London botanical scene, Tall Nightshade Solanum chenopodiodes, which we had found under a railway arch in Lewisham on a previous occasion. This species has only been naturalised in the London area since 1969.
Onwards as the light faded there were only a few more to list including Japanese Honeysuckle Lonicera japonica in Brookmill Park along with Hogweed Heracleum sphondylium, Charlock Sinapsis arvensis and Hemlock Conium maculatum.
At Lewisham Bus Depot our penultimate species was Eastern Rocket Sisymbrium orientale and, yet again, last but not least, on the rail embankment defying an obvious onslaught of herbicide, was Japanese Knotweed Fallopia japonica.
Our total for the day was 86 species representing 25 families. We put the lower total (last year was 93) down to increased tidyness and the loss of those neglected scraps of land so valuable for our urban flora. In addition, and ironically, the warm weather and the continued growth of grass had resulted in late grass cutting lopping the heads off any precocious flora.
We went our separate ways, having thanked Nick for yet another enjoyable winter (despite the temperature) excursion.