500 dead bumblebees – the chemical blitz of modern farming

In September I wrote about the mysterious death of 500 bumblebees. New information has emerged about this incident so I have rewritten the post:

Earlier this year, Sheila Horne was walking at Hacton Parkway, a public park and conservation area in Havering, East London. April is normally a good time to see insects in their prime so she was very surprised to find many dead and dying bees near the path. She alerted local naturalist, Tony Gunton who identified the insects as bumblebee queens from three species, red-tailed, buff-tailed and common carder. This was not a minor incident, there were as many as 500 bees affected.

Chemical analysis of the dead bees

Natural England was appointed to investigate the insect deaths and samples of dead bees were sent to FERA in York for analysis. The results were released in August and showed that the bees were contaminated with the neonicotinoid insecticide imidacloprid and two fungicides, flusilazole and epoxiconazole. Imidacloprid can be very poisonous to bees and bumblebees are more susceptible to this chemical than honeybees. Imidacloprid is currently subject to a two year partial ban for some agricultural uses in the EU. Neither fungicide on its own is especially toxic to bees although flusilazole was phased out this October because of its high toxicity to fish and because of other potential toxic effects.

A nearby field of oil seed rape as the source of the chemicals?

The chemical analysis raises two questions. Where did the bumblebees pick up these chemicals? Were these chemicals responsible for the bee deaths?

Neither question can be answered definitively but as so many dying bees were found together in one place, it seems likely that the source of the poisoning was close by. Hacton Parkway lies alongside arable farmland and at the time of the poisoning some of the land was planted with flowering oil seed rape, so it is a reasonable conclusion that the bees had been feeding there. Because of the chemical analysis, it was initially assumed that the crop had been planted using seed treated with imidacloprid ahead of the ban and that the imidacloprid had killed the bees. Natural England have recently concluded their investigation and found that in fact the seed used to plant the crop had been treated with another neonicotinoid, thiamethoxam. Neither imidacloprid nor epoxiconazole had been used on the crop and the last spraying with flusilazole was in November 2013. Analysis of the dead bees for thiamethoxam failed to detect any of the chemical but this could have been due to losses before the analysis.

What killed the bees?

So, why did these bees die? Because there are so many unanswered questions we cannot be sure. The dead bees were contaminated with imidacloprid but the oil seed rape crop was not the source. We can only assume that the bees fed elsewhere on imidacloprid-treated crops and were flying with this chemical in their systems. It is known that at typical field concentrations, imidacloprid does not kill bumblebees.

There is also the question of how the bees were exposed to the two fungicides if the oil seed rape had not been sprayed with these chemicals during the flowering season. As with the imidacloprid, we have to assume that the bees were exposed elsewhere. It is possible that the fungicides weakened the bees or made them more susceptible to the neonicotinoids. There is some evidence for such interactions for other insecticide/fungicide pairings.

Because the bees died close to the treated crop, the focus of lethality has to be on the thiamethoxam, now known to have been used on the oil seed rape. Although thiamethoxam is indeed an insecticide, there is evidence from one lab-based study and another field study (albeit lacking controls) that, at field-realistic concentrations, thiamethoxam is not lethal to bumblebees. I find it unlikely, therefore, that thiamethoxam alone killed the bees, providing the farmer followed safety guidelines.

We shall never know what actually happened at Hacton Parkway but my best guess is that these bees were flying with the three chemicals in their system and encountered the thiamethoxam-treated oil seed rape. When they fed from it, they picked up the additional neonicotinoid. Two neonicotinoids, with perhaps synergistic effects of the fungicides, were too much and they died.

The investigation is now closed!

The investigation is now closed and it will be impossible to resolve the many questions raised by this incident, which is a pity. Despite this uncertainty, the results of the chemical analysis stand. These bees died with three chemicals in their bodies: one neonicotinoid and two fungicides. They were also exposed to a second neonicotinoid. This was no laboratory experiment; this reflects what is happening around us when these chemicals are used. Have a look at this report to see more evidence of the widespread use of chemicals in UK farming. Our agricultural practices have led to this chemical blitz and the result is the deaths of important pollinators. How often is this occurring on a lower level but not being noticed or reported?

I should like to thank Tony Gunton (local naturalist) and Helen Duggan (Press Officer, Health and Safety Executive) for sharing information about this incident.

A blackbird, some old apple trees and a deserted bench – the garden in November

It’s coming on Christmas,
They’re cutting down trees.
They’re putting up reindeer
And singing songs of joy and peace

From River by Joni Mitchell

It’s only a week or so until the shortest day and, in the town, the Christmas lights have been twinkling merrily since late November. Shop windows struggle under the weight of gifts and expectation and there has been an outbreak of Christmas Fayres in local schools and nearby villages. Totnes will soon host its own festive late-night shopping events. Perhaps all this brashness and brightness is an antidote to the greyness handed out by the recent weather.

Rainbow over Totnes
A rainbow over Totnes church with the Leechwell Garden in the foreground (November 3rd 2014)


My overriding impression this November was a lack of sunshine although there must have been some to produce the rainbow captured in the photograph. We also had our first frosts, waking up to white roofs, and on other days we were buffeted by heavy rain and strong winds which finally disposed of the leaves. The view from my kitchen window changed during the month to one dominated by bare branches.

Crab apple
A detached crab apple and “friend”


Decaying crab apple
A mouldy crab apple


Blackbird on crab apple tree
The predator


Down in the Leechwell Garden, November was a time of seeds and fruits. I remarked a month or so ago on the “almost perfect green spheres tinged subtly with red”, the crab apples. I wondered how these would mature and I now have my answer. By November they were looking distinctly worse for wear and the “green tinged with red” had transmuted to a sickly yellow-orange. Some fruits had fallen off altogether and some were rotting, having been attacked by predators. I discovered the identity of one of the predators as I stood under the tree with my camera. A blackbird landed above me, took a casual peck at one of the fruit and flew off in disgust.





The blackbird may also have been responsible for damage to some chunky overripe rose hips nearby. The same bird will probably be back, when the time is right, to sample the berries offered by a cotoneaster. The shrub already seemed to be spreading its arms to make the berries more accessible.

Chaenomeles fruit and bottle
Fruit of flowering quince, and bottle.


Beneath one of the flowering quinces I found three golden fruit lying on the ground near the old stone wall. Whether they were just overripe or whether the blackbird had been at them, I don’t know. They looked very tempting but I am told that to humans the fruit are unpalatably bitter unless cooked. I deliberately left the bottle in the picture as it highlights one of the problems faced by a public garden. Whereas most people enjoy and respect the Leechwell Garden, a few people see nothing wrong in lobbing a bottle over the wall as a means of convenient disposal.

Perhaps I am being too hard on the blackbird. It has to get its food somewhere and there is an interesting biological chain beginning with sunlight falling on leaves, this energy leading via photosynthesis to tree growth and eventually to fruit which are eaten by the blackbird. Pollinators have a role in there as well. These chains and their relationships feature strongly in the nature writing of Mark Cocker, recently compiled in a new book (Claxton – Field notes from a small planet). Cocker sees the calls of swifts and swallows as a transmutation of “insect protein converted through the birds’ digestive system into the music”. Should I see the chiding call of the blackbird as a transmutation of the photosynthetic activity in the leaves of the crab apple tree?

Fruit on spindle tree
Fruit of spindle tree


Ginkgo tree
Ginkgo glowing


Down in the shadier part of the Garden, the spindle tree continued to light the way. In September, I commented on the shocking pink fruits. By early November, these fruits had opened to reveal bright orange seeds and more gaudiness. By the end of the month, only the pink seed casings remained, looking like tiny ornate lampshades. Another splash of temporary colour came from the ginkgo tree which glowed briefly as though a switch had been flicked and then promptly lost all its leaves.

Mullein flower and hover fly




Bloody cranesbill
Bloody cranesbill




Even this late in the year a few plants seem determined to try to give us colour. Among these survivors were the mullein, still painted in splashes of yellow, some rosemary showing new mauvish-blue blossom and a bloody cranesbill with its small magenta flowers . A borage also had a few blue flowers but they didn’t look properly formed.

Leechwell Bug House

The Leechwell Garden was, for many years, an orchard so it seemed fitting that three apple trees were planted late in the month. Two dessert varieties popular in the 19th century, Laxton’s Superb and Ribston Pippin were planted together with a James Grieve, “the classic Scottish cooking apple” but, in my experience, very good eaten raw. The three varieties seem to have been chosen partly to allow cross pollination but they will need the insects, especially the mason bees from the bug house, to do their bit in the spring.

Deserted bench
The deserted bench. The cup etc surely tell a story ……


The Dorsetshire Gap – a special place

A medieval crossroads, a motorway junction from a former time, a secret spot, a time/space vortex, a geological oddity. These are some of the descriptions of the Dorsetshire Gap, a curious conjunction of ancient trackways and chalk landscape deep in rural Dorset.

The ridgeway track approaching the Dorsetshire Gap

The Dorsetshire Gap is a special and unusual place. Buried in mid-Dorset countryside between Ansty and Folly, it is at least a mile from even minor roads and accessible only on foot. I first came here more than twenty years ago and since then I have been unable to resist the periodic lure of this spot. Earlier this year, under a cloudless, sapphire-blue sky, we approached from the East along a chalk ridge clothed in rough grass and purple punctuations of knapweed and thistles. Encouraged by the midsummer heat, butterflies and bees flitted purposefully between wild flowers and we admired the long, green view northwards over the Blackmore Vale.

The view from the chalk ridge looking towards the Blackmore Vale


Eventually, the path dipped down between trees and through a gate to reveal a flattened clearing, seemingly enclosed by rough woodland and high chalk banks. Looking about, you notice other tracks converging on the same spot from different angles and elevations. One track, from the south, climbs through a clear gap between chalk banks. A prominent four-way signpost gives directions. The Dorsetshire Gap is a complex motorway junction but dating from another age.

[This link gives a map and this link gives the Grid Reference and other location details]

The approach from the East. “The path dipped down between trees and through a gate”


Approaching the Gap from the East in spring. The four-way sign, the box containing the visitor’s book and the chalk banks are visible


The four-way sign and the southern track illustrating the break in the chalk ridge


Geologically speaking, this remote part of Dorset lies at the northern edge of a broad band of chalk that runs south west across the county from the Wiltshire border. Where the chalk ends, it tilts upwards to form a steep escarpment facing the northern clay. This chalk escarpment provides a natural barrier to north/south passage and the Dorsetshire Gap is a break in this ridge allowing access of tracks from the chalky south to the wet claylands of the Blackmore Vale. Other routes, including ancient Ridgeway tracks from Wiltshire and Devon, converge here so that the Dorsetshire Gap is a crossroads, recognised for centuries, where people and animals moving east/west on the Ridgeway were able to access north/south tracks.

The southern track in summer. Note the sunken lane.


How does a place like this arise? No one really knows; how much is natural and how much is man-made is also in dispute. There are numerous earthworks in the vicinity and the remains of a medieval village in the valley below so human influence seems likely. We do know that the Dorsetshire Gap was an important road crossing from the Middle Ages until the 19th century and the paths coming together here are ancient trackways. Some of these trackways may have been used for the movement of goods by packhorse trains, or for the movement of animals by drovers; these practices stopped only with the advent of the railways. If you follow paths westwards from the Gap towards Folly, you eventually reach the road and an isolated house that was formerly an Inn. According to Ralph Wightman this used to be called the Fox Inn and closed only in the mid 20th century. In the past, this may have been a refuge for travellers on the Ridgeway, including drovers and their animals, providing a safe haven for the night.

The westward track rising towards Folly


Several of the trackways are also sunken lanes where tramping feet, heavy hoofs, scraping wheels and foul weather have, over centuries, worn the soft rock away so that the path now lies below the level of the surrounding countryside. Some call these sunken lanes Holloways and further to the west in Dorset there are some striking examples of very deep Holloways. There is a mystique attached to these sunken paths: they are visible remnants of a wilder time, they provide tangible evidence of long forgotten lives and of older ways of travel. Perhaps because of this mystique, Geoffrey Household, in his 1939 novel “Rogue Male”, has his fugitive hero hide in a deep Holloway in west Dorset. Robert McFarlane has written lyrically about these sunken paths and his unsuccessful quest to find Household’s holloway-hideaway north of Chideock.

So what makes the Dorsetshire Gap a special place, one that people write about, one that people actively seek out, one whose name is even inscribed on Ordnance Survey maps?

The four-way sign and the box containing the visitor’s book, in summer


I believe this relates to history and to the power of the imagination. The Dorsetshire Gap has been an important crossroads for hundreds of years. It is an important relic of times past and, as we stand here, we can imagine the sights and sounds of past lives: fragments of conversation from chance meetings, clinking harness as animals are driven through, cries for help as people are robbed, people heading quickly for the ancient drovers’ refuge at Folly. The Gap probably hasn’t changed much over the years so when we visit, we can “slip back out of this modern world” (using the words of W.H. Hudson). Perhaps this is why the Gap has its own visitor’s book. According to Priscilla Houston, the book was first put there in 1972 by a writer known as “Valesman” in the hope that this might help preserve the Gap. For many years it was kept in an old biscuit tin, replaced nowadays by a more secure plastic box. The book allows visitors to record their reflections on visiting this very old, very “Dorset” and very special place.

The visitor’s book


This article appeared in the December edition of the Dorset-based Marshwood Vale Magazine. The photographs were taken by Hazel Strange in Spring 2007 and Summer 2014.

I once knew a man with cardoons ………..

Each week we have a vegetable box delivered to our house and back in August I got a surprise when I collected the week’s box from our front path. A large flower lay across the colourful array of carrots, lettuce, beetroot and other vegetables. I felt a little like Sophie in der Rosenkavalier but this wasn’t a rose; with its spiny stem and its rich burst of purple florets it looked like an artichoke flower. But I was wrong – a neatly printed card told me helpfully that the flower was from a cardoon.

The cardoon flower


A cardoon? I had a vague recollection that this was some kind of exotic vegetable. I looked at the flower more carefully and I could see that the head was smaller and spinier than an artichoke although the colour and shape were quite similar.

Some artichoke flowers


The card told me that the flower was a special gift and, if we wanted to nurture it, we should place it in water in a rustic glass bottle. Rustic glass bottles are in short supply here but we have a rustic-ish vase so that had to do. The purple flower did look beautiful sitting on our kitchen table and I was inspired to find out more.

The cardoon flower in its rustic-ish vase.


The cardoon originated in the Mediterranean region and is grown for its fleshy, leafy stems which feature on menus in France, Italy, Spain and North Africa. It was a popular vegetable in 19th century Britain but has long since fallen out of favour. The cardoon plant can grow to impressive heights and with its spiny, silvery-green foliage it’s worthy of a John Wyndham novel. It’s such an imposing plant that it can also be used to provide ornamental interest to a garden and with its many, showy, purple flowers it is a bee-favourite. When the cardoon is grown as a vegetable, the fleshy stems should be blanched by piling earth around them or by covering them with brown wrapping paper. This removes much of the bitterness that most varieties suffer from. Some people also recommend blanching the prepared stems by boiling in water. I believe there are new less bitter varieties available now.

Guy Watson with cardoons


Cardoons do not come high on most people’s agenda, so how did a cardoon flower find its way to our veg box? The missing link is Guy Watson, the boss of Riverford Organic who deliver our veg box. Watson is a great enthusiast and very keen to try growing forgotten or exotic vegetables. Cardoons are his latest thing and he has grown a small plot of them on his Devon farm. Our gift flower came from this plot and the vegetable has been available to buy this autumn from Riverford. Some nice publicity for his efforts came from Xanthe Clay of the Telegraph who made the pilgrimage to Devon to meet “farmer, veg-box supremo and Martin Shaw-lookalike, Guy Watson” and spent a happy time learning to prepare and cook the sinister vegetable. Xanthe was won over by Guy’s cardoons and asserted that, after removing the stringy bits and cooking until tender, the cardoon is “delicately, addictively delicious, distinctly artichoke-y” and “baked in a creamy, cheesy gratin they tasted sublime”.

Xanthe, you have convinced me. I will try some cardoons when I get a chance but I am still wondering what the relation is between the cardoon and the artichoke. Superficially, the two plants look rather similar but when you get down to the important business of eating them, they are quite different. Globe artichokes are grown for their edible immature flower heads and I can still remember my horror at being presented with an artichoke for the first time in a little restaurant in south west France. Luckily I was with a friend who knew what to do. Artichokes are an important commercial crop in Southern Europe, North Africa, California, South America and China. Cultivated cardoons, as we now know, are grown for their fleshy stems and stalks and are cultivated on a smaller scale in Northern Italy, Spain and Southern France. To complicate matters further, there is another member of the family, the wild cardoon, a smaller, spinier plant that grows in countries around the Mediterranean.

End of season artichoke flower heads


So, how did these seemingly related but actually rather different plants arise? More than twenty years ago, a scientist from the University of Madrid spent some time on this question. She examined a very large number of artichokes, cultivated cardoons and wild cardoons, growing in different locations, looking at their shape and structure. She concluded that all three were variants of the same species Cynara cardunculus. Presumably the artichoke and the cultivated cardoon were derived from the wild cardoon by selection for the desired characteristics. A recent study by a team of scientists from Italy used modern genetic techniques to examine the relationship between the three variants. They concluded that the globe artichoke and the cultivated cardoon were indeed both derived from wild cardoons, probably growing in Sicily or North Africa. Domestication of the artichoke started earlier and was probably under way in Roman times. Domestication of the cultivated cardoon began later but the wild cardoon was also the progenitor.

Let’s finish by returning to the man with the cardoons, Guy Watson. His latest venture is to bring Riverford to London at the Duke of Cambridge pub in Islington. Cardoon fritters have recently been on the menu!

Birches, shaggy ink caps and a wagtail: the October garden

O hushed October morning mild,
Thy leaves have ripened to the fall;
Tomorrow’s wind, if it be wild,
Should waste them all.

(From Robert Frost’s poem October)


Norway Maple in Autumn
The Norway Maple with its orange crown


The beginning of October brought tangible change with alternating periods of heavy rain and cheerful sunshine. I suppose the weather had to shift but I’d got used to the warm and dry. More rain followed and when the remnants of hurricane Gonzalo passed through I saw airborne leaves, gutter-filling leaves and now rotting leaves. It still felt unseasonably mild but despite this, nature moves forward, the flowers have mostly gone and, from my kitchen window, I watched the gradual change in colour as each tree moved ahead but at its own pace. One belligerent punk of a tree (a Norway Maple) tried hard to shock by putting on a bright crown of orange foliage.

Mullein in October
The continuing new growth on the mullein


Honeybee on Mullein
A honeybee enjoying the mullein flowers


Down in the Leechwell Garden I continued to wonder at the tenacity of a mullein which, despite the season, was now a tangled mass of new flowering stems. The fresh, lemon-yellow flowers proved popular with the honeybees now that other forage is becoming scarce.

Mrytle 1
Myrtle: flowers, fruits and leaves

I also discovered a largish evergreen shrub, a myrtle, by one of the old stone walls. It was the brilliant white flowers that first caught my attention, their long yellow-tipped stamens bursting from the petals like a bonfire-night rocket lighting up the sky. The myrtle’s cloak of small, glossy, dark green leaves was complemented by many immature fruits in a variety of colours from pink to green to black. Crushed myrtle leaves emit a eucalyptus-like smell and the berries and leaves are widely used in Mediterranean and Middle Eastern cooking.

A fig tree clothes a large part of the ancient stone wall


Perhaps because of the dearth of flowers, I have spent some time this month looking at the grove of young trees planted near the three mature silver birches. These are a mixture of willows and birches and their height allowed me to look closely at their leaves and fruits. The young birches divide in to two groups, one still covered with large ovate green leaves, the other rapidly losing their smaller, yellowing, diamond-shaped leaves.

Himalayan Birches 1
Four himalayan birches (willows behind)


Himalayan Birch bark
Himalyan birch bark with apricot coloured lenticels


Himalayan Birch bark peeling
Peeling bark on a himalayan birch

The green-leafed birches impress for another reason – their slender, smooth trunks with luminous white bark, characteristic of the Himalayan Birch. On a dull day, the pale, narrow trunks seem to shimmer like ghosts in the gloom. On the upper parts of these trees the bark is peeling away like old wallpaper on a damp wall and, in the past, this white paper-like bark was used for writing Sanskrit scriptures and texts.

Himalayan Birches
Brownish-red markings on one himalayan birch

One of this group of birches also has crazed patterns of dark, brownish red superimposed on the white bark. I didn’t know that Himalayan Birches showed this kind of patterning and it makes me slightly uneasy about my identification.

Male catkins on Himalayan Birch
Male catkins on himalayan birch


Himalyan Birch female fruit and leaf
Seed head on himalayan birch

Around the branches, signs of reproduction and renewal abound. A few chunky male catkins are already present showing their prominent helical structure overpainted in washes of brown and green. In the spring, these catkins will become the familiar pendulous structures brimming with yellow pollen waiting to fertilise the female flowers as they emerge with the new leaves. But the tree hasn’t finished with this year’s cycle and some mature female seed heads are still waiting to discharge their seeds.

Young silver birch
Young silver birch showing reddish pink bark and many mature seed heads

The second group of young birches share many of the features of the three mature silver birches, particularly the foliage. Confusingly, the bark shows varying shades of pink, red and brown but my tree identification book tells me this is typical for young silver birches. New leaf buds are still very small as are the male catkins but this year’s mature female seed heads are very prominent. They fall apart easily if touched, releasing hundreds of seeds.

Male and female fruits on Silver Birch
Seed heads and new male catkins on silver birch

You may already know this, but the birch tree is a Celtic symbol of growth, renewal, stability etc and in Finnish sauna culture, participants gently beat themselves with leafy fragrant boughs of silver birch!

Shaggy Ink Caps
Shaggy Ink Caps

This month’s mild, damp weather has been good for fungi. On the 22nd I came across three fine upstanding shaggy ink caps (Caprinus comatus), also known as Lawyer’s Wig fungi because the bell-shaped cap develops flaking scales that protrude. These ink caps are edible although, I am told, they lack a very distinctive flavour. If you intend to eat them, pick and consume them young as they deteriorate rapidly. They should not be confused with the egg-shaped common ink cap which is poisonous in combination with alcohol.

Grey Wagtail
Grey Wagtail (from a distance)


Writing this diary takes me fairly regularly to the Leechwell Garden. On my visits, there has always been something to look at in the Garden, something to remark on, with one exception: birds. Why do I see so few birds, I don’t have an answer. So, it was a pleasant surprise to encounter an interesting bird this month as I walked away from the Garden towards the Leechwell. I saw the bird ahead of me as its flight traced an arc from the water to the wall above. When it reached the relative safety of the wall, it bounced about before settling; its habitual tail flicks and sleek shape told me immediately that this was a wagtail. I could see flashes of lemon yellow so this was most likely the resident, water-loving grey wagtail. It was there again a few days later. So, there are some birds about!

Autumn sculptures
Some “autumn sculptures” I found in the Garden one day.

Chemistry and politics at the time of the First World War

The terrible conflict of the First World War changed life for everyone in the UK. Few could have predicted, however, that a quiet backwater in rural Dorset in the South West of the country would become a secret First World War explosives centre which would provide vital support for troops and have an indirect influence on the formation of the state of Israel. This is the story of the Royal Naval Cordite Factory at Holton Heath.

A century ago, when the First World War began, Holton Heath, near Wareham in Dorset was a quiet tract of heathland bordering Poole Harbour. Within a year everything had changed and the heath had been transformed into a busy construction site for the highly secret Royal Naval Cordite Factory. This factory provided critical support for ammunition production for the Navy during WW1 and again during WW2. The site was finally closed in 1997 and is now partly a nature reserve and partly a business park.

What was cordite?

In 1914, all bullets and shells used by British forces depended on cordite as a propellant. Cordite was packed in to ammunition and once ignited, produced hot gases whose pressure propelled the shell or bullet towards its target. Cordite was made by mixing the viscous liquid nitroglycerine with fibrous guncotton (nitrocellulose), a little petroleum jelly and the solvent acetone to form a paste. This paste was extruded through a hydraulic press to produced spaghetti-like strands of cordite which were dried and cut to convenient lengths for use in ammunition.

Brisanzgranate 1 db.jpg
A World War I shell showing the cordite strands used as propellent (from Wikimedia Commons)


Superficially, this sounds like a simple process but don’t forget that the WW1 conflict was on a scale previously unimagined. This placed huge demands on cordite production requiring industrial-scale chemistry to make the raw materials. Many of these were potentially explosive so that there were great risks for workers.

Preparing strands of cordite during WW2 (from the Imperial War Museum © IWM (A 24936))


The Royal Naval Cordite Factory at Holton Heath

The main administrative buildings at the Royal Naval Cordite Factory Holton Heath


In 1914, Winston Churchill, then First Lord of the Admiralty, decided that the Navy needed its own protected supply of cordite; perhaps he foresaw problems with supply. He commissioned building a factory to produce cordite exclusively for the Navy and a search began for a suitable site. Holton Heath was finally chosen because it was away from centres of population but with good transport links by rail and by sea. Work began in 1915 and the factory opened the following year. The site employed more than a thousand people during WW1 and Holton Heath station was built to help people get to work. Many of the workers were women, the so-called munitionettes, and the steam trains carrying staff to work were nicknamed “glamour puffers”. We should not, however, underestimate the courage of these women. They were performing dangerous work, they were handling explosive materials and they were exposed to toxic chemicals. They risked their lives every day and their work could be seen as an echo of the lives of the men fighting abroad.

The Holton Heath station sign as it is nowadays (photo kindly donated by Pat English (http://squirrelbasket.wordpress.com/))
Holton Heath Station
Holton Heath Station as it is nowadays (from Wikimedia Commons)

The acetone crisis and Chaim Weizmann

Acetone was a critical ingredient in the manufacture of cordite and the scale of the conflict meant that huge amounts of the chemical were required. At the start of the war, acetone was imported from the major timber growing countries of the United States, Canada and Austria where it was made by distillation from wood. By 1915 there were supply problems and it became clear that another source would be needed to satisfy the huge demand of the munitions industry. The Synthetic Products Company in the UK tried to produce acetone on a large scale using bacteria to break down potato starch but ultimately failed to deliver the amounts required.

Weizmann's passport photo.jpg
Chaim Weizmann’s passport photo 1915 (from Wikimedia Commons)

The solution to the acetone problem was supplied by a Russian Jewish immigrant, Chaim Weizmann, working in the chemistry department of the University of Manchester. Weizmann was an expert in what we now call biotechnology, the use of biological processes to perform chemical transformations. He had collaborated with the Synthetic Products Company in their work on bacteria but eventually they parted company and he worked alone. After several frustrating years of research between 1912 and 1914 he finally isolated a bacterium that would produce acetone from maize starch in good yield. This microbe came to be called “Clostridium aceto-butylicum Weizmann” and provided the answer to the acetone problem.

Weizmann’s work had been performed on a small scale in the lab but, in 1915, when the Admiralty heard about his findings, they asked him to try to scale up the process. This was done in stages, first in a former gin factory in London and then in a 15,000 gallon tank built specially at Holton Heath. Weizmann must have paid regular visits to Dorset at this time to oversee progress. The work went well and the Admiralty decided to build a full scale acetone plant at Holton Heath employing Weizmann’s process. The new facility generated 2000 tons of acetone a year from maize starch. The success of the work in Dorset encouraged the Ministry of Munitions to adopt Weizmann’s process for production of cordite required for ammunition for all British forces.

Weizmann’s work on acetone, much of which was implemented in Dorset, was, therefore, fundamental to the outcome of the First World War. It was also the first application of industrial biotechnology, the use of biological systems to make valuable products on a large scale, now widely used for the production of drugs and vaccines.

Weizmann and Zionism

Flag of Israel


Flickr - Government Press Office (GPO) - President Chaim Weizmann.jpg
Weizmann in 1949 (from Wikimedia Commons)


Weizmann was a passionate Zionist and in 1917, became President of the British Zionist Federation. His principal wish was that the Jewish people should return to their homeland. The contribution he made to the war effort put him in a unique position of respect and influence. Although he was not a member of government, he knew and was respected by many of the politicians of the time. His views would have been listened to and he had long discussions with the Foreign Secretary Arthur Balfour. Indeed it was Balfour who in 1917 issued a Declaration supporting Palestine as a national home for the Jewish people. Israel was established in 1948, Weizmann was its first President and chemistry had influenced politics. The Royal Naval Cordite Factory in Dorset was inextricably interwoven with these events which still reverberate.

Some of the old buildings of the Cordite Factory as they are nowadays (photo kindly donated by Pat English (http://squirrelbasket.wordpress.com/))


The image featured at the top of this post is of a tract of nearby heath called Arne Heath.  It is how I imagine Holton Heath looked before the factory was built.  The image is © copyright Graham Horn and licensed for reuse under this Creative Commons Licence.

This article appeared in the October edition of the Marshwood Vale Magazine.

For another article on this factory see Squirrel Basket.

More ivy, more Ivy Bees !

Last Sunday, we enjoyed a walk around the small Devon seaside town of Salcombe. It’s a pleasant place now that the season is over and we relished the views over the estuary on this cooler but dry day. I don’t know whether I am looking more carefully or perhaps I haven’t previously visited Salcombe at this time of year? I didn’t remember the profusion of flowering ivy.

The Salcombe estuary on a sunnier day, viewed from the cliffs (Photo by Hazel Strange)


A narrow coast road links the town to its two beaches, North Sands and South Sands. On one side of this road there are low cliffs dropping to the sea and all along the cliff tops were huge banks of ivy. Given my recent experience, I now search any stand of flowering ivy for Ivy Bees and the Salcombe cliffs did not disappoint.

Ivy bee on ivy Salcombe 3

Wasps were the predominant insect on the ivy flowers but there were also quite a few of the sleek, slender, yellow and black-banded Ivy Bees (Colletes hederae) with their characteristic russet hairs. The wasps mostly tolerated their company although I did see one attack an Ivy Bee. The bee fell away but I could not be sure if it died or just sloped off.

Ivy bee on ivy Salcombe 2

The Ivy Bees at this site seemed to be moving about less than when I had seen them before. Once they had found a suitable flower head they spent some time exhaustively probing its flowers. Perhaps there was more pollen and nectar available? Perhaps it was cooler? I looked for colonies but did not locate any; I presume the nests are in nearby cliffs but as these are mostly private land they are out of bounds to Ivy Bee-nerds like me.

Ivy bees on ivy Salcombe

What I am beginning to realise is that, in this part of Devon, Colletes hederae is doing rather well with large colonies and large numbers. They also don’t seem to mind the cooler damper weather we have been experiencing.

It’s good to have a positive bee story to tell.

We visited Salcombe on October 12th 2014.

For those interested in Ivy Bees, they featured in the Guardian Country Diary this week


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