Snake in the grass

It was time for the annual Viper's-grass monitoring, so Andy and I headed to Dorset for a couple of days.  If you are not familiar with British plants, the name Viper's-grass is misleading: Scorzonera humilis has nothing to do with snakes and it is not a grass.  It is a relative of dandelions and is one of our rarest plants, restricted to two sites in Dorset and two in Wales.  Next year it will celebrate its centenary as a British plant.  It was discovered here in 1914 by Noel Sandwith when he was only twelve.  A couple of years later he was given a day off school to show it to G C Druce, the doyen of British botany and one of the most fanatical plant listers of all time.

Before we continued the count the next morning, Rob, our reptile licensee, took us out to survey some real vipers on the heath.  The sun was rarely showing itself, and despite it being almost the end of May, the weather was still stuck at the end of January.  There were no reptiles basking on the track sides, but under the tins we found a couple of baby Slow-worms Anguis fragilis.

Every time Rob turned over a tin I was hoping to see my first Smooth Snake Coronella austriaca.  Eventually my hopes were fulfilled as the lid was lifted on a large male, which Rob estimated was about fifteen years old.

We could see that it was indeed smooth, its scales lacking the keel down the middle that you find on other snakes.  There were no more snakes on the heath, but around the farm there were more Slow-worms and a fine female Adder Vipera berus.

The Smooth Snake, which feeds mostly on other reptiles, including smaller Smooth Snakes, is at home on the heath, but Adders are rarely found there.  This is perhaps because there are not enough small mammals for them to eat.  We found another Adder in a nearby large garden, as well as a Grass Snake and more Slow-worms.  Having seen all the British snakes within an hour, we returned to the Viper's-grass field for more counting.

The cold weather made it hard to find insects, but Andy had a good find under some dung, with the very shiny scarab Trypocopris pyrenaeus.  The surface of this beetle is smooth and almost mirror-like, more so than in any of our other large dung beetles.

To be certain of the identification you can flip the beetle over and look at the under side of the abdomen, which has small pits and hairs at the side, but is smooth in the middle.  The slightly less shiny Trypocopris vernalis has hairs and pits all across the abdomen.

Kleidocerys ericae, a bug that lives on heather, was about, but we did not find many other insects, so it was left to a plant to provide us with another highlight.  Pale Dog-violet Viola lactea is a scarce species of heathlands in the south-west, but it is sporadic in its appearance.  It can remain dormant under gorse for years, waiting to flower when the spiky canopy above it is removed.  Last year I saw it respond to a fire on Anglesey that had taken out large areas of gorse.  Here at Stoborough it usually appears where gorse is cut back, and we found a few plants by the track in an open area.

By the time I get out to the heaths, the flowers are usually fading or gone, but after the slow start to spring, there were several in full bloom for us to admire this year.

After dark II: In praise of pine

At the reserve this afternoon I noticed a lot of ant beetles Thanasimus formicarius running about on some pine logs.  I thought this should mean that i) there are lots of deadwood beetles about, and ii) tonight would be the time to look for them because the hot day would have made them active.

The ant beetles were still out when I returned after dark.  It is getting tiresome to mention Nalassus laevioctostriatus, but as usual it was everywhere.  The big pine logs also had two big weevils: Hylobius abietis and Pissodes pini.  The larger of the two, Hylobius abietis, is a common pest in conifer plantations.  Pissodes pini is a widespread but local weevil, commoner further north.  I have seen it in native pine woods in Scotland, but this is the first I have found in England.  Pine is often demonised in England.  In Scotland it is romanticised in the Forest of Caledon, the defining component of native pinewood, to be cherished and protected.  In England it is seen as an invader and a nuisance on heaths and in broad-leaved woodland.  Is this right?  Scots Pine Pinus sylvestris was a native tree throughout Britain until the climate warmed after the last ice age and it retreated north.  How long did it persist in the south?  It cannot have been common, but if you look at the records favourably, it is possible that it held on in England and Wales until only a few hundred years ago, its extinction being hastened by forest clearance.  This would give it the same status as beaver, wolf, or lynx, which are considered lost natives whose return would be welcomed by some and called a conservation success after millions of pounds had been spent on making it happen.  As far as I can see, the only difference between those species and Scots Pine is that Scots Pine has recolonised its former range for free, and it has been so successful that it needs to be controlled (and that last part could apply to any of the animals if they were brought back).  We need to keep controlling pine, but I do not think we should seek to extirpate it or always see it as a non-native bad thing, and we should celebrate the many animals and fungi that it brings with it.

The next target was birch.  No deadwood beetles here, but there were lots of Aradus depressus, a weird looking and very flat bug.

The highlight of the night was on a tall, standing, dead Beech.  This is a splendid tree, with a hollow base and large Ganoderma bracket fungi growing inside and out.  It looks as though it should be home to rare deadwood beetles, and a sprite or two, and tonight I found one on it (a beetle, not a sprite).   Any click beetle with black elytra and red pronotum is going to be something good, and this one turned out to be Ischnodes sanguinicollis, a very scarce insect found in rotting wood of various trees.

Although most people see the reserve as a heathland site, its deadwood fauna is just as important, perhaps even more so, and we must not neglect it.

Purple

Several people had told me that the display of Pasque Flowers Pulsatilla vulgaris at Therfield Heath this year was one of the best they had ever seen.  So on a sunny day Col and I went over after work to check out the purple.  We were a little late in the season, but it was a beautiful evening, and there were thousands of flowers on the side of the hill, filtering the evening sun through their sepals.

Looking east, the hill was dotted with purple flowers, each with a blaze of yellow stamens at its centre.

To the west, against the light, there was a haze of delicate mauve and white, as the hairs on the leaves and stalks gave each plant a halo.

Pasque Flowers are such special things.  They grow in chalk grassland, where they keep the best of company.  At Therfield Heath they share the turf with Hairy Violets Viola hirta, and later in the year, the fruiting heads, which are just as spectacular as the flowers, will stand above Bastard Toadflax Thesium humifusum, another rare (but much less showy) plant.  We were a little late to catch them at their best.  There is a short time in every Pasque Flower's life when its blooms are open enough to expose the golden stamens, but its sepals are still deep purple enough to create a startling contrast with them.  Soon the flowers fade to lilac, still pleasing, but not so garish.

It had been a warm day, and this seemed to have brought out the smaller of our two bloody-nosed beetles Timarcha goettingensis in good numbers; there were singles and pairs all over the grass.  Andy Schofield called this Britain's dopiest beetle, and they do have the air of an insect that is not in a hurry and has no great concerns in the world.  If they do come across something to rouse them into distress, they exude a spot of red fluid from their head and hope that whatever has forced them to divert from their languid state will go away.