Wednesday 16 September 2020

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

Tuesday 15 September 2020

'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.                          

Sunday 13 September 2020

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?



Tuesday 1 September 2020

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.






Monday 31 August 2020

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!














Friday 28 August 2020

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?




Saturday 22 August 2020

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.