Meadow yellow

Meadow yellow
Bulbous Buttercup (Ranunculus bulbosus) in a Devon meadow

Thursday, 27 May 2010

Close shave for Twayblades

Today I went to look for a local green orchid, the Common Twayblade (Listera ovata). It is probably named “from Old Norse, since the modern Swedish name is TvĂ„ Blad - two leaves” - Typically plants have two dark green oval leaves (1).

This particular plant has been saved from the ‘cut’ by a local botanist, having been topped a few weeks ago by a council mower. It has been protected from further damage with sticks and tape. Our Council seems to have a growing obsession with scything our local roadside verges and hedgebanks. Maybe people prefer green grass monotony or barren banks scraped to the earth. Clearly there needs to be some maintenance, but why so zealous? What is sacrificed for this ‘clean’ countryside approach is a razzmatazz of wild flowers. The plants that have adapted to this manmade habitat are many of our woodland flowers utilising the shade of hedgerows or overhanging trees, and other meadows plants
using the more open aspects. These plants also provide food and cover for many of our invertebrates. Locals have also spent the last seven years protecting a ‘colony’ of Six-spot Burnet (Zygaena filipendulae) moths on the verge opposite to the Twayblades, feeding on the richness of Knapweed, Trefoil and Vetches.

However we are in danger of losing much of this bonus biodiversity. It takes up to 15 years for a Twayblade plant to reach maturity from seed(1), making it hard to rectify damaging actions. Ironically there is evidence that the Common Twayblade rather enjoys manmade habitats(2), but I doubt this is true where the ‘countryside hairdressers’ are allowed to run riot with their blades.

(1) Britain’s Orchids (
(2) Nowicka-Falkowska, K. (2002) Ecology of selected populations of Listera ovata (L.) Br. from Siedlce environs. Acta Scientiarum Polonorum - Biologia, 1(1): 23-32

Friday, 21 May 2010

Hawthorn styles

It’s the time of the May-flower or Hawthorn (Crataegus monogyna). The hedges and country lanes about my home are now full of their white blossom true to their name. This is a plant full of mystery, such as a link to the early Christians who associated it with Joseph of Arimathea (owner of the tomb given up to Jesus after the crucifixion) (1); It is said that he visited Glastonbury where he planted a staff that sprouted to produce a ‘Holy Thorn’ that blooms around Christmas time, and from which cuttings have grown and still occur in the area (2).

But until this spring I was unaware of another, more botanical mystery. Mary, a local botanist popped in to see me this week with a cutting from what she called ‘Two-styles Hawthorn’. This is actually an alternative name for the Midland Hawthorn (Crataegus laevigata), although I prefer its more apt original name. This is a less common species of hawthorn and is characterised by having two or three styles compared with the Common Hawthorn’s single style (hence the second part of its Latin name, monogyna). During the autumn they can still be distinguished by crushing the ‘haws’ and counting the seeds; if there is more than one seed it will be a Midland Hawthorn, reflecting the flowers style number. Its leaves are also different with the lobes far more rounded and less deeply cut to the mid-rib. It is true that it occurs commonly across much of the Midlands, but it is also as frequent in the South East. However beware as the differences can get rather blurred as they frequently cross to produce hybrids. Otherwise the Midland Hawthorn tends to bloom earlier and prefer more shaded woodland.

So next time you are admiring may blossom, have a closer look and check out the styles. It gets a bit addictive - although my neighbours are getting increasingly suspicious of my actions.

(1) Filed Guide to Trees and Shrubs of Britain (Reader’s Digest Nature Lover’s Library)

Friday, 7 May 2010

Poisonous claws and gonopods

I’ve recently attended two courses looking at invertebrates, and focussed on the ultimate ‘creepy crawlers’, millipedes and centipedes; the many legged creatures that derive their names from the Latin for foot, ‘pedis’.

It’s been fascinating looking in detail at these mini-beasts, including poisonous claws and gonopods (genitalia). There is frequent confusion between the two groups, with an assumption that millipedes have many more legs than centipedes. This is true in some cases, but the key differences are that Millipedes have two legs per body segment (hence their classification as Diplopoda), whereas centipedes have only one (Chilopoda). Otherwise there is great variety in leg numbers, even within species, from the fast surface scurrying ‘stone centipedes’ (Lithobius species - see image above) with 15 pairs to long winding ‘earth centipedes’ (Geophilomorpha) with up to 101 pairs. Millipedes include those that roll up into a tight ball (the Pill Millipede, Glomeris marginata) , and the snake millipedes with their numerous legs enabling them to glide over the surface like their namesake and also often curl into snake like spirals when disturbed. All centipedes are carnivorous using their poisonous claws, an adapted leg, to immobilise their prey. In contrast the millipedes are primarily feeders of leaf litter and dead wood, playing an important role in breaking down leaf litter. The millipedes can also be long lived, such as the Pill Millipede which has been recorded as living for 11 years (*).

The best places to find them are under logs & stones and in leaf litter in woods and gardens. I've found all the above types in my garden in the last two days. Just lift up pot or stone and see what’s there – but please don’t forget to place things back to where you moved them from as you may destroy a mini-home and its long-term tenants.

*To identify and read more about these animals and many others that can be found in similar places, try ‘Animals under logs and stones’ by C.Philip Wheater & Helen Read (Naturalist Handbook series, number 22).