14-May London’s Last Wild Edges

Waterside edges and marshy areas are also now rich in wild flowers. Attractive species such as bog bean, ragged robin, fritillary, water violet, marsh valerian and water avens are all worth seeking out. Water avens can sometimes be found growing beside herb Bennet, with every different intermediate hybrid between them also present. It has a very unusual flower colour and perfectly heart-shaped petals. Its petals are an unusual mixture of orange, red and purple and its roots are also pleasantly aromatic. They used to be added to ale to prevent it getting sour. More commonly encountered flowers by water are yellow flag, comfrey, mare’s tail, watercress and brooklime. Water crowfoot demands clear running water, which thankfully still exists along some parts of the river Wandle and the river Mole where it still can be found.

Although not a river plant, meadow saxifrage Saxifraga granulata can be found in the old water meadow beside the Thames facing Ham House. This handsome plant has also been recorded from a churchyard in Sanderstead for over a century. At the edges of country lanes, cow parsley and stitchwort still dominate. Occasionally you now start to see black and white bryony as well as honeysuckle. Old walls are always worth examining, especially in the spring. Ivy-leaved toadflax and yellow corydalis are common, and the equally attractive diminutive rue-leaved saxifrage S. tridactylites less so. Although small, this saxifrage dramatically stands out when its leaves go a vivid deep red.

Rarer plants worth seeking out this month include hound’s tongue Cynoglossum officinale and salisfy Tragopogon porrifolius. Hound’s tongue prefers to grow where there are lots of rabbits. It is left by the rabbits as it has a mousy smell, which they seem to find distasteful. Fortunately it produces hooked fruits at just the right height to become hooked onto foxes, when they stalk the rabbits.

Salsify has such attractive purple flowers it is grown as an ornamental as well as for its edible roots, which for some taste of oysters. It occasionally turns up elsewhere, often with its close relation – goat’s beard T. pratensis. One of the great May rarities is purple gromwell Lithospermum purureocaeruleum. Its flowers start off red and end up a piercing gentian blue. Sadly it is now confined in the wild to one or two sites in the West country but it can still usually be seen in the gardens of South London Botanical Institute.

The best way to get familiar with the biodiversity that exists in London is to visit as many different habitats that you can and May is a good month to start. The reason for this is that each habitat has its own precise fauna and flora and quite often its own rarities. Luckily for Londoners inside a twenty-five mile radius of its centre there is a huge number of different habitats although it has to be admitted many are severely reduced in size or degraded. There are, of course, habitats we are unable to visit such as railway embankments, quarries, reservoirs, sewage farms and chalk pits and others such as mountain, maritime and coastal habitats that just don’t exist in our area. Fortunately there are still many left that we can visit.

London is particularly rich in different kinds of woodland both ancient and secondary with Epping forest possessing a particularly large list. Although most of our woods are often dominated by English oak, Lesnes Abbey wood is predominately made up of Sessile oak. Some exceptional beechwoods still exist in the Downe and Titsey area and exceptional wet woods along the river Colne e.g. Denham Lock wood. Other rare woods include the yew wood in Norbury Park and Box wood on Box hill but the most biodiverse has to be the area of ancient wood pasture that still remains in Windsor Great park. There is also still a good range of grassland habitats e.g. acid (Wanstead flats), calcareous (Epsom downs), meadows (Totteridge fields), pasture (Islip manor) and grazing marshes at Wennington and Aveley. There are also both wet heaths e.g. at Oxshott and Esher and dry heaths at Walton and Chobham common.

Perhaps the easiest way to visit a good range of habitats is to walk some of the capital’s more rural footpaths e.g. the London Outer Orbital footpath or Loop, the North Down’s way or one with a different geology such as parts of the Greensand Way near London. The Thames path is also to be recommended as is the Wey Navigational canal leading on to Basingstoke canal. Other habitats worth making an effort to visit include the Ingrebourne Valley for its reedbeds, Frays farm for its fen, Wimbledon Common for its well hidden Farm bog, Chertsey Meads for its flooded meadows, West Kent Golf course for its chalkland flora and perhaps some of the northern tributaries of the river Lea for any gin clear chalk streams that may have survived.

Springs have several unusual creatures associated with them but nearly all in London seem to be either capped or culverted. You can still see a more accessible spring on Keston Common and nearby in the grounds of the Holwood estate there are still springs rich in species. Even some cemeteries and parks are much more species diverse than you might expect e.g. Abney park cemetery and Syon Park, home of the exceptionally rare German hairy snail Perforatella rubiginosa. Even Ruxley Gravel pits boasts over five hundred different beetles.