Great Central Woodland

Time was when Woodford Halse was a small village - and then came the Great Central Railway. It had a huge motive power depot (An M.P.D. was invariably referred to as a 'shed' by railway enthusiasts) and its activities came to dominate life in the village. Indeed, it developed into a town and the railway was by far the main employer.

Woodford Halse shed in its latter years. Probably
around 1958

All that has gone but the huge area of raised land where the shed stood can still be clearly seen. Beside this mound is an area of low-lying, heavily vegetated wasteland and this has been adopted by the community. Often it is quite wet but recent weather has left the area very dry, so when I visited it on 15 September the vegetation was not at its best.

www.greatcentralwoodland.org reads the notice board

From the heart of the village the visitor crosses the infant River Cherwell. In places it was choked with debris but heavy rain should cause the river to rise and clear this material.

Currently the River Cherwell is rather noisome.
15 September, 2020

Insects were not abundant, or at least they were keeping a low profile. Doubtless there were many at the plant-soil interface. However there was plentiful evidence of insect activity.

The gall of Urophora cardui on Creeping Thistle. Great 
Central Woodland, Woodford Halse. 15 September, 2020

.

The Creeping Thistle (and occasionally other thistles too) sometimes develops a rather globular swelling on the stem. It is formed by the larvae of a so-called Picture-winged Fly, in this case, Urophora cardui.

More evidence of insect activity was this discoloured patch on a poplar leaf. In this case the insect responsible is an agromyzid fly, Agromyza albitarsis. It may be quite common but few records have been submitted for mapping.

This greenish patch on a poplar leaf will eventually become
 brown. It is the work of Agromyza albitarsis.  Great Central 
Woodland, Woodford Halse. 15 September, 2020

Yet another leaf mine on poplar was formed, in this case, by a moth. The Poplar Bent-wing, Phyllocnistis unipunctella, is one of the micro-moths and its larvae form silvery mines looking vaguely like snail trails.

Vague, rather silvery mines are formed by the larva of
the Poplar Bent-wing. Great Central Woodland again,
15 September, 2020

I confess that my visit was rather disappointing but giver the exceptionally dry conditions this is understandable. Certainly it is worth another look in more favourable times.

Tony White. e-mail: diaea@yahoo.co.uk

'Tis the season...

 ...for Shaggy Parasols, Chlorophyllum rhacodes. In fact three species go by the name of Shaggy Parasol but the one we meet on our walks is invariably this one.

The Shaggy Parasol, Christchurch Drive, Daventry.
8 September, 2020

The gills are pale

The shaggy scales on the cap are distinctive but it is worth taking a look at the pale gills.

The species has a reputation for being  good eating and so it is - for most people. But apparently about 1 in 40 get an unpleasant reaction from consuming them. Certainly I have never bothered, not least because most that I have found are in places where dogs are frequently walked. Enough said!   

The generic name means 'green-leaved', strange for an organism that has no leaves, green or otherwise. In fact the word has also been used in the sense of being 'green-gilled' and there is a poisonous alien species, Chlorophyllum molybdites with green gills and therein perhaps lies the explanation.                          

False Acacias

Daventry is well blessed with False Acacia, Robinia pseudacacia, trees, and they are particularly prominent around the car park beside The Newlands, i.e. around the Aldi car park.

False Acacias beside The Newland, Daventry.

                                                     8 September, 2020                                                                                             

Their graceful pinnate leaves are typical of many other members of the Fabaceae such as the true acacias and of Laburnum. In spring they were covered in cream pom-pom flowers, much visited by bees. Despite belonging to the same family as the true acacias, and having a broadly similar appearance, they are not really closely related.

The flowers hang in racemes

The flowers have now given way to the fruit in the form of long brown pods and numerous seedlings have developed around the trees. In warmer climates such as southern France, Italy and Spain the trees have become something of a nuisance, springing up in inappropriate places.

The trees are intensively planted in many parts of the world and apparently 250,000 hectares of them have now been planted in Hungary. Obviously their timber could be of use but their honey is much prized and when rambling in France I have often seen roadside signs advertising miel d'acacia.

The pods start off green but become golden-brown.
The Newlands, Daventry

A feature of the tree, sometimes called the Black Locust,  which appeals to me is the gnarled, twisted appearance of the trunk and branches, making even a young tree appear venerable. In Northampton and elsewhere False Acacias are host to mistletoe plants and the combination of a gnarled appearance with a garnish of mistletoe can be quite striking.

False Acacia and mistletoe - not, I hasten to add, the
specimens in Northampton.

The False Acacias bearing mistletoe are in Weston Favell near to The Trumpet pub. May we hope to see this sort of sight in Daventry?

Green Elfcup - minus the cups

I visited our local pocket park - Stefen Hill Pocket Park - today. It was, by my calculations, the umpteenth visit and yet, as usual, there was a story.


A rotting tree stump, familiar to scores of children and dog walkers, stands beside the perimeter footpath. Recent rains have made it sodden and the texture of the wood now resembles balsa. I carefully lifted some of this material and was pleased to expose a patch stained a copper sulphate sort of blue-green.

I recognised it as the stain formed by the Green Elfcup, Chlorociboria aeruginascens. I will keep an eye on the tree stump because, although the staining is not uncommon the fruiting bodies do not often appear - and they are rather spectacular. This fungus was once used to provide the colour for Tunbridge Ware pottery.

The Green Elfcup is not often seen in its fruiting form.

A child was walking nearby with her mother. After whispering to Mum she came over and shyly asked if she could show me something she had found on a leaf. I strolled over to the shrub in question and she showed me what had been puzzling her.

Harlequin ladybirds are all-too common. The larvae are easily seen at

this time of the year. Stefen Hill Pocket Park. 31 August, 2020

I explained that it was a ladybird. Both child and mother were clearly unconvinced so I explained to them, outlining a little about larvae and metamorphosis before telling them that it would turn into a Harlequin Ladybird. Both were clearly surprised. There is surely a place for schools having a decent garden or area of uncultivated ground for kids to get to know these fundamentals. (Although 70 years ago I, the same age then as this child, probably didn't know. I had no one to tell me.) I am certain that teachers are more knowledgeable today in many matters but that doesn't really make up for a lack of wild places.

Anyway, insects and other wildlife in parks and gardens is now dreadfully limited and I didn't find much else of note. I was a little surprised to find the leaves of Cherry (Prunus sp.) attacked by what appears to be Firethorn Leafminer, Phyllonorycter leucographella. It will attack beech but is generally confined to rosaceous trees such as pyracantha, rowan, apple, cotoneaster and so on. Of course cherry is in the rose family too but this is the first time I have seen it mined by this moth.

The Firethorn Leafminer is very common on Firethorn but is less

frequent on cherry. Stefen Hill Pocket Park. 31 August, 2020

Incidentally, the Firethorn Leafminer was first recorded in Britain as recently as 1989 but has clearly spread quickly and is a real nuisance to growers.

Timken and beyond

Yesterday Chris and I visited our daughter Jacqui and her husband Dean, who are currently living in an area of Daventry known as Timken.


The very wet and chilly weather of the last few days is beginning to abate and, following an excellent lunch we decided a constitutional walk was in order. It is not an area I know particularly well and I was pleasantly surprised by what I saw.


First up, and only ten metres into our walk was a Windmill Palm, Trachycarpus fortunei, also known as the Chusan Palm. It might be assumed that it was introduced into Europe from China by Robert Fortune, but in fact Philip von Siebold introduced it in 1830, beating Fortune by 19 years. If a male and female are grown then fruit may be produced but they are not considered edible.

Chinese Windmill Palm, Rowallen Way, Daventry.

30 August, 2020

A little further on was a patch of Bittersweet, aka Woody Nightshade, Solanum dulcamara. 'Nothing exciting about that,' I hear you mutter. And that is true, but the leaves had been mined by the little moth, Acrolepia autumnitella. This species, known as the Bittersweet Fanner, is quite common in this area but becomes scarce further north and seems to be unknown in Lancashire and Yorkshire - or indeed anywhere in the north of Britain.

Bittersweet leaves mined by the larvae of a tiny moth, the Bittersweet

Fanner. Furnace Drive, Daventry. 30 August, 2020

Although the larvae in their leaf mines are frequently seen the adult is elusive. Certainly I have never found it when I have had a camera handy. Incidentally I found the mines some years ago on Deadly Nightshade in Northampton.




The larvae of Acrolepia autumnitella feed on Woody Nightshade.

Here is the imago. Photo courtesy of British Moths.

Our walk took us to the track bed of the former Daventry to Leamington railway line, now a popular footpath in this area.




Looking west. Leamington only 30 miles away!

A curious fungus was growing on an old tree stump beside the footpath.

What is it? See Postscript

 

It was sprawling across nearby twigs, looking rather like a tatty piece of polystyrene. Perhaps it had been nibbled by slugs. I spent a few moments examining and photographing it and when I turned round Chris and Jacqui were disappearing into the distance towards the site of the old railway station (sadly no longer existing - as far as I know). Bing was trotting alongside, pausing awhile to sniff.



L to R: Bing, Chris, Jacqui.

There were no rarities to be seen. In fact everything was decidedly commonplace, but I always like to see Spindle, Euonymus europaeus, as it is scarce on the acid soils of the Daventry area.

Spindle bears curiously lobed fruit. Waste ground, Daventry.

30 August, 2020



Ropes of Black Bryony, Tamus communis, looking like some sort of liana, hung from wayside trees. It is Britain's only member of the Dioscoreaceae, the Yam Family. All parts of the plants are poisonous. The fruits are tempting to children but cause a severe blistering of the mouth if eaten. (There is a second bryony in Britain. Known as the White Bryony it is completely unrelated to Black Bryony but, despite being in the Cucumber family, Cucurbitaceae, it is also poisonous.)

Tempting but poisonous, the succulent fruits of Black Bryony beside a

disused railway track in Daventry. 30 August, 2020

Finally across Daneholme Park, a feature I had not previously visited. It contains some fine trees including some oaks from North America. Quercus palustris is confusingly known in the U.S.A. as Common Sallow.

The leaves of Quercus palustris are like a deeply jagged version of an

English Oak. Daneholme Park, Daventry. 30 August, 2020

I failed to find any acorns so my identification could be at fault - but it gives me an excuse to go back and take another look.


Postscript  After posting a picture of the fungus on Facebook I received advice that it was an old Laetiporus sulphurous, known as Chicken of the Wood. Edible and tasty I am told - but not in that state!

Sawfly surprise

Byfield Pocket Park again. Well, you never quite know what will turn up.


For those not familiar with sawflies, they are hymenoptera and thus related to bees, wasps and ants. And they are difficult! No concise book exists on the identification of the British species and students of these often common insects depend on consulting a range of books, articles and the examination of reliable labelled collections for the accurate naming of specimens. I generally ignore them and set them free if any find their way into my sweep net.


Fortunately some are common, widespread and easily recognised, so when I found a group of their caterpillar-like larvae in their characteristic pose on a birch sapling I recognised them immediately as Birch Sawflies, Cimbex femoratus. Except that when I got home I realised I was quite wrong.


I hadn't even bothered to take a specimen but fortunately I'd taken a number of not-very-good photographs. As explained, sawflies are not my thing but as soon as I examined the photographs I realised that my original assumption had been unforgivably hasty. So what was it?

The caterpillars of Pristiphora testacea in a characteristic pose.

Byfield Pocket Park. 27 August, 2020

After trawling through a couple of books and web sites without success It became clear that it wasn't a common or garden species. Fortunately I knew the foodplant so that narrowed things down considerably. Any road, as my mother would say, six books later I did eventually identify it as Pristiphora testacea. An examination of the N.B.N.(National Biodiversity Network) maps on-line showed only eleven records for the species in Britain but unfortunately these maps rely on records being submitted - and not all are. Nevertheless, this seems to be a genuinely scarce species.

What else? Yellow Toadflax, Linaria vulgaris was present in a neglected flower bed. It is common of course but is a cheerful little plant, much visited by bees and a new species for the site.

Yellow, or Common. Toadflax. Byfield Pocket Park. 27 August, 2020

Greater Plantain, Plantago major, was also new but of more interest was the mine of a fly, Phytomyza plantaginis, on its leaves.

Phytomyza plantaginis seems to feed on any plantain species.

Byfield Pocket Park. 27 August, 2020

And now to go through all the other insects found during my visit. More surprises perhaps?

The eyes have it

At the request of the parish council I have, for about a month now, been recording insects and other arthropods from a scruffy and neglected patch of ground adjacent to Byfield Pocket Park. As one might expect, the species recorded have been mundane and rather predictable. But a couple of days ago I recorded my first surprise.


Stomorhina lunata is known as the Locust Blowfly. It is related to blowflies and in warmer climates is known to be a predator on the eggs pods of locusts and large grasshoppers. It is tempting to believe that it preys on British grasshoppers in a similar manner but there seems no evidence that this is the case.

The Locust Blowfly has turned up in Byfield Pocket Park

With its striped eyes and rather long 'snout' it is a striking insect and I had never previously found a specimen. It is a 'first' for Northamptonshire.

Also striking, and found nearby a few minutes later, was Coreomacera marginata. The name Sieve-winged Snailkiller has been coined for this and is, I suppose, reasonably appropriate. It is a member of the Sciomyzidae, a family of snail-killing flies. It will be seen that this species also has striped eyes even though this, and the Locust blowfly are only distantly related.




Coremacera marginata was also present in the pocket park.

Photograph: Jessica Joachim

Eyes with this kind of banding are to be found in several groups of diptera (two-winged flies) with several clegs (species of Haematopota). Of course, as a rule people seeing one of these on their body quickly slap them before they bite! The Notch-horned Cleg, Haematopota pluvialis, has also been recorded from this site. The species is all-too common.

Many a country walker has received a bite from Haematopota pluvialis

Eristalinus sepulchralis is rather different, having spotted rather than banded eyes. I find it occasionally, usually in damp areas, but it is not particularly common and has not been found at the Byfield site.

Eristalinus sepulchralis is from yet another family. It is a hoverfly and

therefore a member of the Syrphidae

As for Eristalinus taeniops, the Band-eyed Drone fly, I have never found it - nor am I likely to now although it does occur in Mediterranean countries.

Eristalis taeniops has a wide range, but has not reached Britain.

In recent years a number of flies have been moving northwards, a situation generally ascribed to climate change. This is what has happened with Stomorhina lunata, the fly with which I started this blog. So the Band-eyed Drone Fly could make an appearance...but I won't hold my breath.

Indian Bean Tree

The last school at which I taught had, in its grounds, a very large Indian Bean Tree, Catalpa bignonioides. In July it bore masses of its lovely flowers - cream, with yellow and purple markings in the throat. One day a child drew my attention to dozens (maybe hundreds) of honey bees struggling on the ground beneath the tree. They appeared to be intoxicated; drunk on the possibly fermented nectar from the flowers. The phenomenon of bees intoxicated by fermented nectar is well-documented from hundreds of such incidents.

Catalpa bignonioides has sumptuous flowers

I recalled this incident yesterday when I saw one of these trees in a garden near to Stefen Hill Pocket Park. Only having an inadequate little camera with me, and unable to get very near I took a picture, unsatisfactory but just able to show the hanging pods which give the tree its name.

The thin, pencil-like fruits are distinctive. Near Stefen Hill Pocket Park,

Daventry. 20 August, 2020

It is a native of the southern U.S.A. and occurs on Florida and adjacent states, so the 'Indians' of the common name refers to the indigenous people of the region, not to India. The native people of the area were Cherokees, so Cherokee Bean Tree would be a more appropriate name.

I have examine the pods of this species in many places over the years but have yet to find a properly-formed seed, so the species may be self-sterile. Reaching up to 60 metres in height it is too big for the average suburban garden but for those able to do so it is tempting to grow a specimen.

It is a member of the Bignoniaceae, a very important family that includes the lovely Jacaranda Tree, Jacaranda mimosaefolia and the Sausage Tree, Kigelia africana, whose extraordinary fruits 'are indeed like big fat salamis hanging from the rafters of some Italian kitchen' (Tudge, 2006). They make the fruits of the Indian Bean Tree look positively emaciated.

The Sausage Tree, Kigelia africana occurs through much of tropical Africa.

Back to Catalpa. There are about eight species found across East Asia, North America and the West Indies yet C. bignonioides seems to be the only species much seen in Britain. This is a surprise, for others in the genus, such as C. bungei, also seem very fine - and hardy too.

Catalpa bungei, a native of northern China.

British gardeners are a conservative lot.

Reference

Tudge, Colin 2006 The Secret Life of Trees  Penguin Books

Hornbeam

I have, for some time, been considering a blog on the subject of the Hornbeam, Carpinus betulus. There seems no logical reason for this as it is not a spectacular tree in terms of fruit, foliage or dimensions - at least, not in the Daventry area. Perhaps its most interesting feature, for me at least, are its catkin-like fruiting spikes, looking vaguely like hops. Alas, when I went to photograph some a couple of weeks ago they were well beyond their best.

This female catkin, rather high in a tree, was the only specimen I could

find. Byfield Pocket Park, 16 August, 2020

These catkins would be easily overlooked were it not for the leafy enlarged bracts more or less surrounding the fruit, which takes the form of a nutlet. This photograph, taken by Walter Obermayer, is far clearer than I could achieve.

A better view. Photograph by Walter Obermayer

So, is there nothing else of interest? Certainly the wood is the hardest, heaviest and toughest of our native trees (in parts of Norfolk it was once known as 'hardbeam') and in the past was put to use as axles on carts, or indeed, any moving parts. However it apparently decays quickly when exposed and was well-known for not taking creosote (and the sale of creosote-treated wood is banned anyway). Hornbeam forms a good garden hedge and in a fastigiate form is often seen as a street-tree in, for example, Banbury and Northampton.

Hornbeams are frequently used as an amenity tree, especially in a

fastigiate form

In Northamptonshire the Hornbeam is right in the edge of its range as a native tree and according to the latest Northamptonshire flora (Ref. 1) only occasionally found. This contrasts with the observations of John Gerard (1545-1612) who wrote, in 1597: 'The Hornbeame tree groweth plentifully in Northamptonshire'. (Ref.2) The best place to see it in the county today would seem to be Yardley Chase.


Although some botanists have placed the Hornbeam genus in its own family, the Carpinaceae, most now regard it as a member of the Birch family, Betulaceae. Carpinus is the original Latin name for the Hornbeam but some etymologists believe it derives from the Celtic name for an ox-yoke - indicating perhaps another of its uses.


I hinted in the opening paragraph that large trees were found beyond Northamptonshire. In Epping Forest, to the north-east of London, are some magnificent hornbeam pollards, a number of which are more than 200 years old and conceivably over 300 years of age.

Fine pollarded specimens are to be found in Epping Forest

There are around 30-40 species occurring across the Northern Hemisphere, all apparently confined to temperate regions. Some of them are very picturesque and I would like to see a well-grown specimen of Carpinus japonica.

Carpinus japonica is sometimes known as the Chinese Lantern tree,

( despite its specific name!).

When covered with its catkins it must be an arresting sight yet, despite being perfectly hardy, it seems to be not often grown.

References

1. Gent, Gill and Wilson, Rob (2012) The Flora of Northamptonshire and the Soke of Peterborough  Robert Wilson Designs


2. Gerard, John (1547) The Generall Historie of Plantes (usually simply known as 'Gerard's Herbal.

Birches

I made a visit earlier today to Byfield Pocket Park with the intention of continuing my survey of an adjacent patch of what had been sheep-grazed meadow. It covers no more than 1500 square metres and should be a straightforward job but it has become seriously overgrown. Furthermore there had been heavy rain overnight and the whole area, with its long grass and nettles was absolutely drenched.

I turned my attention instead to the Silver Birch trees, Betula pendula. There are between six and half a dozen  (Don't be silly. Ed.) of these in the pocket park, some doubtless planted but other probably arriving via their wind borne fruits.

There are about six birches in Byfield Pocket Park.

17 August, 2020

The fruits develop as catkins and I carefully split open and examined some of these. Tiny flies, species of Semudobia, attack the seeds within the fruit and I was pleased to find evidence of Semudobia tarda.

The seeds are frequently attacked by Semudobia species, in this case

Semudobia tarda.

The fruit should be winged, allowing the seed to be carried a considerable distance. When attacked by S. tarda the wing fails to develop. I found several fruits attacked in this way. The finding of this species was pleasing as I had already found Semudobia betulae in a nearby tree a few years ago. 

It came as no surprise when a Birch Shieldbug, Elasmostethus interstinctus, dropped into my sweep net a couple of minutes later. It very much resembles the more familiar Hawthorn Shieldbug, Acanthosoma haemorrhoidale, but is clearly smaller.

Birch Shieldbugs, surprise, surprise, are common on birches.

Byfield Pocket park, 17 August, 2020

The Silver Birches were proving to be home to several quite interesting insects and this was to be expected as the tree is native to Britain, however a birch clearly of an exotic origin was also present and had clearly been planted.

It bore no label but its white bark was peeling, making it likely to be either Betula papyrifera and B. jacquemontii.

Betula jacquemontii? Byfield Pocket Park, 17 August, 2020

The foliage isn't terribly helpful as the leaves of both species are very similar. I decided it was B. jacquemontii with the confidence in my identification, on a scale of 1 to 10, of about 1.

The leaves were of little help.

The loose bark, when peeled back, revealed a pair of Common Earwigs, Forficula auricularia, their rather straight forceps showing them to be female. (Those of the male are far more curved.)

Female earwigs have rather straight pincers. Byfield Pocket Park,

17 August, 2020

More interesting was a harvestman. The manner in which its legs were spread-eagled in a near-parallel manner showed that it was Dicranopalpus ramosus. This species, originally known from Morocco, was first found in Britain in 1970 but is now very widespread; today it was the commonest species in the pocket park. The name Dicranopalpus refers to the long apophysis on the pedipalps, giving them a forked appearance. The word ramosus also means 'branched' so here we have an example of nomenclatural tautology; there are dozens of these in biology.

Dicranopalpus ramosus on birch bark. Byfield Pocket Park,

17 August, 2020

Also swept from a birch was a specimen of the Common Furniture Beetle, Anobium punctatum. It is quickly recognised by the oddly-shaped head, sometimes described as resembling a monk's cowl. The adults do not feed but it is the larvae which bore into wood, with distinctive and catastrophic results.

If you can't find an old table or chair a birch tree will do. Anobium punctatum was

present at Byfield Pocket Park. 17 August, 2020 

A tiny black weevil, Apion simile, was present in large numbers and I have another dozen or so insects to be checked, all taken in barely half an hour. Over the seasons this figure could be at least quadrupled because I have not yet looked at aphids or the larvae of moths. The Silver Birch is graceful, tough, and a home to a great range of insects. And, incidentally, mycologists love birches too for the range of fungi it supports when dying and in death. Where would we be without it!