A common rough woodlouse

On emerging from our back door today after a second spell of cold and snow, the first thing that caught my eye was a woodlouse about a metre up on the wall.  Not exactly a sheltered position but one that perhaps gathers some heat from the kitchen behind.

Woodlice (or isopods) are interesting subjects of study for those who like invertebrates.  There is a manageable number - nearly 40 British natives or outdoor breeders (and a few more in greenhouses) -and, unlike many invertebrates they are around all the time and can often be found just as easily in summer as in winter.  They also have an interesting range of parasitoids and predators, do not sting or bite, cannot be classed as pests and are easy to collect and keep alive.  Identification is fairly straightforward with the AIDGAP guide A key to the Woodlice of Britain and Ireland by Stephen Hopkin and published by the Field Studies Council.  There is also a British Myriapod and Isopod Group which promotes the study of these and some other invertebrate groups: http://www.bmig.org.uk/

The woodlouse in the picture on our wall above is the common rough woodlouse, Porcellio scaber, a very common species in the British Isles.  The orange bases of the antennae in this example is a frequent feature of this species.

A few spring flowers

Between bouts of cold the earliest spring flowers are starting to bloom.  There are a few anemones in the woods and the new growth of dog's mercury is a bright glossy green.  In a woodland garden near home I noticed one clump of daffodils.  They look like wild daffodils (Narcissus pseudo-narcissus) and do not appear to be part of any organized garden.  So far as I could see they are the only clump of daffodils in this area and they seem to have spread from one bulb.  If so I wonder how they got there.

It might be slightly too large for the true species, but the characteristic two-toned flowers have the wildlings slightly downward drooping habit.

Other minor pleasures include the first celandines and a dandelion in flower.

Snowball pink

The Beast from the East as the bitterly cold Siberian anticyclone has been dubbed brought heavy snow showers this morning.

Just outside our window were the skeletal remains of a Deptford pink (Dianthus armeria) with each grey brown shuttlecock of seed head delicately holding up a small ball of snow like a supplicant making an offering.  This pink has been surviving as a self sown annual in our garden for maybe 30 years and needs no looking after.  It often seeds itself into pots of other plants where it can be left as its slender shoots do not mask the main attraction.  Then, in summer, it produces a sequence of small dark pink flowers.

There is a fine appreciation of this modest native flower by Andy Byfield here: https://www.theguardian.com/lifeandstyle/2012/jun/21/deptford-pink-plantlife

The lane in the cold

Along the lane they have been cutting the hedge by machine (permissible until 1st March).  The rather brutal results with shredded wood and white broken branches harmonises well with the bitterly cold wind from Siberia.  It reminds me of of Totes Meer, the painting by Paul Nash: http://www.tate.org.uk/art/artworks/nash-totes-meer-dead-sea-n05717

There are some very Gothic shapes among the battered bushes, especially where the hedge is thin, but I expect it will all fill out quite nicely.  The other day we had a visitor from Alberta in Canada and she asked why we had hedges round our fields instead of fences - that gave me an opportunity to hold forth on the English landscape and its conservation.

Despite the frigid weather and brutal hedging work, there were some signs of spring in the lane.  Patches of snowdrops, little 'tommies' (Crocus tommasinianus) escaping from our neighbour's garden and a few flowers on lesser periwinkle.

Knapweed phyllaries

Yesterday I received my copy of the BSBI News from the Botanical Society of the British Isles.  It has been redesigned and has a new editor - Andrew Branson - and the results in my view are excellent, though I shall always have fond memories of reading and writing for the previous version under the editorship of Gwynn Ellis.

One article that interested me was "Ambiguity in recording Centaurea (knapweeds) taxa using MapMate".  This had coloured pictures of the phyllaries of what are considered to be the three British species (C. nigra var. nigra, C. nigra var. nemoralis and C. jacea) though it pointed out that hybrids were common.  ('Phyllaries' are the small leafy structures, or bracts, that surround the base of the flower/seed head.)

I immediately pulled on my boots and set off to my favorite patch of 'old' meadow where I found plenty of knapweed seed heads still perched on stiff, dead stems above the fallen grass.  These were plainly the nominate subspecies Centaurea nigra var. nigra.

A wonderful excuse to do some useful botanising in winter and to remind oneself on what to look forward to when summer returns.

A mid-January walk

The weather was warmer today with the sun shining and no rain.  Heading down the garden I found that the spurge laurel (Daphne laureola) had opened some of its flowers.  The bush appeared here of its own accord and the next nearest example I know of is about 500 metres away in a wood and the plant seems nowhere common in this part of East Sussex.

Further down the garden I found our bush of the winter flowering honeysuckle Lonicera x purpusii 'Winter Beauty' and was pleased to discover that the flowers were being attended by a couple of rather dark marmalade flies, Episyrphus balteatus. This very common hoverfly often appears here in the colder months and its presence on the honeysuckle again illustrates how important these winter flowering introductions can be to our native fauna.  Lonicera x purpusii is a hybrid between two Chinese species and I wonder what Chinese insects may be attracted to their flowers.

In Churchland Wood I photographed this single-stemmed hornbeam.  These trees are nearly always coppiced, but there are two or three that have been left to grow naturally in the wood and I often wonder why.  Maybe there was a use for larger pieces of the wood.

Underneath the trees the green leaves of bluebells are rising through the leaves as a reminder that spring is not far away.  Noise levels are increasing too with, today, several great tits calling loudly and a great spotted woodpecker drumming on an oak tree.

Invertebrates on witch hazel flowers

We have a witch hazel bush halfway down the garden making a fine show with its bright yellow, sweetly scented flowers contrasting with the cold and damp.

In 1993 I wrote a note (about the same garden) for the Entomologist's Record: Nocturnal invertebrates visiting flowers of Witch Hazels, Hamamelis mollis pallida and Hamamelis japonica cultivars, in January and I have posted an edited version here:

On 20th January 1993 I walked around our garden with a torch and inspected our Wintersweet, Chimonanthus fragrans and Witch Hazel, Hamamelis mollis pallida bushes both of which were in full bloom with their sweetly scented, pale flowers.

I found nothing on the Wintersweet, but the Witch Hazel had a variety of Diptera (two-winged flies) on the flowers. There was the mosquito Culiseta annulata quite clearly feeding; two species of fruit fly (Drosophilidae), Parascaptomyza pallida and Drosophila subobscura, the latter the more common of the two; an Anthomyiid and the Common Yellow Dung-fly, Scathophaga stercoraria.  Culiseta annulata, with its distinctive white-banded legs, in one of our commonest mosquitoes and is often found in winter in outhouses or caves.  Parascaptomyza pallida is also an extremely common fly that seems to be about in most months of the year.

On 30th January 1993 I again inspected the Hamamelis mollis pallida and also two H. japonica cultivars, "Primavera" and "Arnold" after dark. The flowers were attracting numerous invertebrates including woodlice, millipedes and spiders. Insects noted were the Common Earwig, Forficula auricularia (Dermaptera: Forficulidae); an owl fly (Dipt.: Psychodidae); Sepsis fulgens (Dipt.: Sepsidae); a Pherbellia sp. (Dipt.: Sciomyzidae); Tephrochlamys rufiventris (Dipt.: Heleomyzidae); Dromius linearis (Col.: Carabidae) and a brown Noctuid moth caterpillar.

The centre part of the Witch Hazel flower seems to be constructed for insect pollination and is relatively flat and open allowing easy access to the nectaries by short-tongued species. The pollen is sticky and, in the flowers I examined closely, had been successfully transferred from anthers to styles. Most of our Witch Hazels usually set a good quantity of viable seed and it would appear that they are adapted to pollination by nocturnal invertebrates. On day-time visits I have found only Sepsis fulgens and two non-biting midges, Smittia aterrima and Limnophyes prolongatus. The last two were, I suspect, simply sheltering in the bushes rather than feeding on nectar.

Another Stereum crust fungus

In my post on January 11th I posted a picture of a resupinate orange crust fungus.  I think this was probably Stereum hirsutum.

Today I found a much more luxuriant colony of what I think is probably the same species in Killingan Wood (TQ783192).  There is much fallen wood in this area, but only one - a large ash branch - carries such a display of fruiting bodies.

Winter mixed with spring

On a wind chill walk today I found the first expanded hazel catkins: always a sign to me that the wildlife season has started (though it never really finishes of course).  Soon the hedges will be thick with these catkins shedding their pale yellow pollen.

Also on hazel, this time on dead, usually standing, trunks is the common and widespread ascomycete fungus known as hazel woodwart (Hypoxylon fuscum).

In the very sheltered Killingan Wood brick pit I found precocious flowers on a primrose and beside it on the wet leaves a dead male mottled umber moth (Erannis defoliaria) a winter-flying species whose season is nearly over.  It used to be very common when I was young, but is thought to have declined in recent years.  Like the winter moth, the females have very reduced wings useless for flight.

January miscellanea

Although the countryside is bleak grey-green washed by a cold winter wind, there are still moments of brightness.  One of the best is the flowers on the gorse hedge that runs across Churchland Fields.  In warmer weather these scented golden blossoms attract bees and other insects, but it is too cold for any to be on the wing at the moment.

There are a few splashes of colour provided by fungi like this resupinate Stereum species on a a chestnut trunk that was cut down last March.

Or purple jellydisc (Ascocoryne sarcoides) growing here on a dead, but upright hornbeam trunk in Killingan Wood.  This was kindly identified by Nick Aplin via the Sussex Fungi Group

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On the fauna side, one of our daughters spotted a well-camouflaged green caterpillar on a fern leaf that was pressed against our kitchen window pane.  The nearest look-alike I can find is the larva of the copper underwing (Amphipyra pyramidea).  There appears to be some feeding damage on the pinnae of the fern but the copper underwing should be a pupa at this time of year.  One fern-feeding noctuid is the small angle shades (Euplexia lucipara), but it isn't that.  It seems to enjoy its place between glass and frond, so I will leaves it to see what happens.

We seem to be experiencing a minor population explosion of what I think is the amphipod landhopper Arcitalitrus dorrieni.  This is a native of forests in New South Wales, Australia, but has become widespread here.  It occurs frequently in gardens and the pair of dead ones illustrated here were found on our sitting room floor - the first time we have seen the creatures indoors.  In life they are normally darker coloured than this.

A memory of Rosebank

At Christmas in 2017 I came across this photograph which I had taken nearly ten years previously on 4 April 2008.  I had forgotten that I was ever there and would not have remembered where it was had I not been able to find details of my visit buried in my computer.  At first, I had no idea about when or why I had taken the picture, but I gathered fragmented recollections after a while.

The picture was taken looking east from an abandoned depot or lorry park called Rosebank beside the A22 just north of Polegate in East Sussex.  The fields run down to the Glynleigh Levels, a western branch of the larger Pevensey Levels, and the distant horizon is where the village of Hankham lies on a spur of higher land projecting northwards into the levels.  In the past it was spelt 'Handcombe' and was part of a 'Limb of the Cinque Port Liberty of Hastings'.  In the mid-distance the dark, straight hedge marks the line of the Cuckoo Trail, a cycle and pedestrian path along an abandoned track of the London-Brighton South Coast Railway.

This is a Low Weald landscape with little to excite the imagination: fields and trees (with a tree house), a Shetland pony, various fences and, on the left, a water-filled clay pit dug when the long-closed brickworks nearby was active.  Perhaps the significance of the scene is that it would not win any prizes, would not embellish the wall of a gallery or the page of a magazine.  Its somewhat nondescript virtues do, perhaps, have a Low Weald feel.

It is also represents only a fragment of time.  The camera shutter was open for maybe 100th of a second and that exact scene will never return.  It might be possible to go back to the site and frame a similar picture, but it would not be the same.  The pony would have gone, the tree house might not be there and the trees and fences would have changed.  And who knows what alteration might come over centuries and millennia?

The picture reminds me too of the huge volume of data that lies locked up in our brains because there is no reason or no one to open the door.  I have posted the picture in ‘the Cloud’, so others may look at it for one reason or another, but they will not have the memories I had of the afternoon I spent alone in that forgotten depot, recording the flora and fauna and its ecological significance for a proposed development.  As Virgil said sunt lacrimae rerum et mentem mortalia tangunt (there are tears in things and life’s transience moves the mind).

Bumblebees on Camellias

Now that mild weather has returned to East Sussex, a few bumblebees are on the wing again in the garden.  This is, as far as I can tell, a queen buff-tailed bumble bee (Bombus terrestris) photographed this morning.  The single-flowered pink camellia is Camellia x williamsii 'J. C. Williams' which usually starts flowering here in December and is very popular with bees at a time when many of the mahonias are going over.

It must have been thought of by others, but I wonder if these light-sleeping queens that find nectar and pollen sources when they wake up in mild spells in winter are getting an evolutionary advantage.  In the past, when there were few, or no sources of nectar in the countryside, light sleepers would have been at a disadvantage, but now camellias, mahonias and other winter-flowering exotics are common in gardens, the light-sleepers may be getting a survival advantage over those who do not wake up until primrose time.  Perhaps a more attractive idea than that it is all due to global warming.

Midwinter pleasures

Despite the mild and rather drab days we are having, I find much to ponder in my short walks round the neighbourhood.  I was entranced by two trees, a birch and a field maple, the latter still holding its leaves..

It led me to Robert Frost's poem about birches in which, among much else, he says:

I’d like to go by climbing a birch tree,

And climb black branches up a snow-white trunk

Toward heaven, till the tree could bear no more,

But dipped its top and set me down again.

 I also liked the phrase by poet Marchant Barron where he describes the golden-yellow leaves of the field maple "as if touched by Midas in the season of alchemy."

In Killingan Wood, which seems very brown and quiet at this time of year I noticed some almost military lines of slime-mould fruiting bodies on a log.

Later in Churchland Wood I found an extraordinary sky blue 'lichen' (below).  I wondered if something had happened to a normally grey or green species to cause this and will try to find out more.  On 23 December my friend Howard Matcham suggested it might be cobalt crust fungus, Terana caerulea this seems a possibility, but it has also been suggested that it could blue paint that somehow was splashed on this branchlet.  I do not think it is paint as there is only a small quantity here and searching as I do almost every day I would have been likely to see anything marked with such bright blue elsewhere.

Shieldbug in liverwort

In Churchland Wood (TQ782189) I found a circular patch of green liverwort two metres up on the smooth trunk of a sweet chestnut.  After an exchange of emails with my old friend Howard Matcham it was identified as dilated scalewort (Frullania dilatata), a species which I am more familiar with in its brownish purple form.  It is quite common in our area.

I brought a small piece home with me and, to my surprise, discovered a tiny shieldbug nymph nestling among the fronds.  It is an overwintering forest bug (Pentatoma rufipes) - one of the few species that overwinters here as a nymph - and quite how it normally gets through the winter has been a subject of some speculation.

Roger Hawkins in his book Shieldbugs of Surrey. (Surrey Wildlife Trust, 2003) says "The Forest Bug is unusual in that it passes the winter as a small nymph, high up on the bark of forest trees."  There follows a discussion of the various things these nymphs might feed on and materials such as tree sap, small invertebrates and honeydew are cited.  Southwood & Leston in their Land and Water Bugs of the British Isles say "it is not known if the first instar larvae feed.  The second instar larvae feed, but the nature of their food is not understood."

 It seems to me that, among other things, they might well be sucking the contents of the leafy lobes of some of these tree hugging liverworts, especially as they are well-camouflaged in such situations.  The liverwort pads are also not well-placed for insectivorous birds to explore and contain a variety of small invertebrates such as springtails and mites that would vary the bug nymph's diet.

As another twist I learnt that Frullania dilatata and F. tamarisci cause a dermatitis known as 'woodcutter's eczema' and it occurred to me that the bug nymphs, if they are sucking the sap, may be building up some sort of chemical defence against predators.

On ivy berries

The berries on our native ivy seem to be ripe already.

This is quite early for them, often they will not be ripe until well into spring.  There are many birds that eat the berries though the seeds pass through their gut (seed dispersers).  Woodpigeons are also very fond of them but they digest the seeds (seed predators).  The fruits are nutritious with a high fat content but they are toxic, though birds normally seem to be able to deal with the toxins.  Barbara and David Snow in their splendid book Birds and Berries (T & A D Poyser, Calton, Staffordshire. 1988) say that woodpigeons destroy most of the ivy berry crop.

We also have a bush of arborescent Persian ivy (Hedera colchica) but the seeds on this are still unripe.  It makes a non-climbing dome-shaped bush about two metres high that is convenient for watching the various insects that gather on the blossoms in the autumn.

One conundrum regarding ivy berries concerns the holly blue butterfly (Celastrina argiolus).  Many books say that the larvae feed on these berries among those of other plants.  Jeremy Thomas, for example, says in his Butterflies of  Britain and Ireland (1991) that "larger ivy berries may also be completely devoured, but the cups remain as evidence."  He also says the eggs of the summer generation are laid on ivy buds.  The larvae occur in May and June and August and September so they are not normally present when there is any appreciable crop of ivy berries and I wonder if the flower buds are sometimes confused with fruit.  Whether buds or berries, holly blue larvae eat the insides rather than the outsides and the 'cups' to which Jeremy Thomas refers must be the outer layer of the buds (or fruit) as they do not have cups like acorns.

Richard South in his classic 1915 The Butterflies of the British Isles quotes extensively from a paper by Adkin describing how the second brood larvae tackle ivy buds, saying in conclusion that they quit the buds in order to pupate.

Cold snap December 2017

It has been very cold over most of the country.  Last night the temperature fell in our garden to -2.6 C but in Shropshire -13 C was recorded.  The thin layer of snow that remained from yesterday froze hard and produced a lovely crunchy surface on the dead leaves in Churchland Wood.  It was like walking over crisps.

Blackbird, munchkin and snow

Our granddaughter has recently cleared the area outside our kitchen window between the path to the backdoor and the hedge as part of our intermittent attempts to manage it as a mini nature reserve.  A couple of days ago we put a small slightly rotten orange pumpkin (sold as a munchkin) in the centre of the area.  I bought in October as a small gesture towards Halloween and wanted to watch what would happen to it as it decomposed.  Yesterday the female blackbird at the top of the picture put in an appearance and was flicking leaves over in search of food.  Among other things she found fallen berries from the nearby rock whitebeam tree (Sorbus rupicola).  Her activities started to bury the munchkin (which she did not touch) with a layer of leaves and I reflected that birds must often help objects laying on the surface slowly to get covered up and buried.

Today we had our first snow of the winter accompanied by much hysteria on TV.  We caught a snow belt that moved in from northern France (closing the port of Calais) but we were right on the edge and it all melted quite quickly.  However, I think it is one of the coldest spell we have had in December for a long time.  The photo is a wider shot of the munchkin area much patronised by Mrs. Blackbird and, today, her mate.

On wingless females

Yesterday evening a male winter moth (Operophtera brumata) was attracted to the light from our kitchen window pane.

I know it is a male because the females are micropterous - almost wingless - and unable to fly.  In the past when I arrived home by car in winter I would often see dozens of males fluttering in the headlights along woodland lanes, but they do not seem to have been so common recently.

As a small boy, friends and I used to look for females of this species and mottled umber moths on the bases of tree trunks and in Canada I once saw several males similar to the winter moth fluttering round the base of a tree trunk where there were wingless females.

I used to wonder why some insects had this wingless female dimension.  Other examples are the vapourer moth and the autumn flying cranefly Tipula pagana.  The best explanation I have come across is by Malcolm Scoble in his book The Lepidoptera and I think it worth quoting at length:

Wing reduction is strongly related to environmental conditions.  Those few species where males are affected inhabit coastal habitats or small oceanic islands, areas where wind conditions are such as to prevent individuals flying directionally towards potential mates.  Jumping is a typical mode of progression in members of these species.  Wing reduction in females is strongly related to the degree of egg maturation at eclosion.  Well developed eggs leave little room for the flight muscles, which become reduced.  Reduction of flight muscles leads to flightlessness, a first stage in wing reduction,  Tympanal organs, which occur mainly at the base of the thorax or of the abdomen, also tend to become reduced or lost.  Females emerging from the pupa with well developed eggs have no need to sustain themselves while the eggs mature.  As long as males can find them, and provided eclosion occurs on a suitable foodplant, these females can lay their eggs rapidly.  Species exhibiting these characteristics are often active in the cold season (e.g. many Geometridae) where rapid oviposition, occurring before extreme conditions overtake individuals, is clearly advantageous.

In other words you can mate and lay all your eggs before you and your partner freeze to death and, since it is winter, you may be less likely to be eaten by a bird.

Reference: Scoble, Malcolm J. (1992)  The Lepidoptera.  Natural History Museum Publications, Oxford University Press

Late flying moth

A yellow-line quaker moth (Agrochola macilenta) settled on the outside of our kitchen window yesterday night.  It is an autumn-flying species, but rather infrequently recorded as late as December.  It is said to be attracted to decaying apples.  A. macilenta is a widespread species in England with larvae that feed on a variety of deciduous trees or, in the north, heather (Calluna).

The adult moth is rather sparingly and inconspicuously patterned (macilenta means 'lean' or 'meagre' referring to the markings), they are however distinctive especially the yellow and red almost straight submarginal lines that do not quite make it in good order to the wing tip.

Winter bumbles

On milder days the flowers on the Oregon grapes in the garden are attractive to late flying bumble bees.  The example above is, as far as I can tell, a buff-tailed bumble bee (Bombus terrestris) worker.  One feature of this is that it has a very narrow band of buff hairs between the black and white bands at the end of the abdomen.  The species is also known to have a third, winter-flying generation whose workers visit oregon grape and other winter flowering shrubs.

This Oregon grape is Mahonia x media 'Charity' which originated in a nursery in Northern Ireland and was selected in a Surrey nursery.  We have several different Mahonia species and hybrids in the garden but 'Charity' is among the most attractive.  The fruit of Oregon grapes can be used to make jams, jellies and in other recipes.  It has both an Award of Merit and a First Class Certificate from the Royal Horticultural Society, so it ticks nearly all the boxes: ornamental evergreen foliage and fragrant flowers in winter; edible fruit; attractive to wildlife.