Powered by Plants

Guest, Keen & Nettlefolds (GKN), Winterbourne House and Garden, Digging for Dirt

Guest, Keen & Nettlefolds (GKN)

Before his marriage to Margaret, and the construction of their family home, Winterbourne’s John Nettlefold cut his teeth in the family firm which eventually became Guest, Keen and Nettlefolds (GKN), one of the largest manufacturing companies of its time, first forged in the heat of the industrial revolution. John began work in the firm’s Broad Street offices before taking charge of a Welsh steelworks in Rogerstone near Newport, Monmouthshire. As heavy industry boomed, board members, realising the need for an improved supply of coking and steam coal to feed their burgeoning operations, identified the acquisition of collieries as a central strategic policy. At the peak of their influence in Wales, GKN produced over 6 million tons of coal and employed 36,000 men concerned with its extraction and use.

Today, these former industrial heartlands look very different and coal is no longer ubiquitous in our lives; deep mining communities in Wales were ravaged by pit closures in the 1980s, the once iconic Flying Scotsman locomotive makes only a handful of appearances a year, and Winterbourne’s open fires are stoked only on very special occasions. Despite this demise, every year hundreds of toy steam enthusiasts descend upon Winterbourne to pay homage to the technology of a bygone age. Faced with the mechanised world it spurned, it is easy to forget that coal conceals a simpler, biological past. Indeed, the industrial revolution, and in turn the wealth behind Winterbourne, were in fact, powered by plants.

Toy Steam Day, Winterbourne House and Garden, Digging for Dirt

Toy Steam Day, Winterbourne House and Garden

The same coal which fuelled Victorian and Edwardian England was formed when plants growing 295 to 320 million years ago shed leaves and limbs. These were then preserved and, through a complex process, later transformed into sedimentary rock. During the Carboniferous period all of the land on earth was joined together in one super continent called Pangea, which was so large it stretched virtually from one pole to another. The climate in the northern and southernmost points was extremely cold. Temperatures rose incrementally in relation to the equator and those parts of the continent which represented present day North America and Northern Europe, where the bulk of coal forests thrived, experienced similar levels of heat and rainfall as a tropical rainforest might today.

“Coal mining areas have historically been rich sources of fossils, particularly plants from the Carboniferous period. Huge amounts of material was extracted and provided access for fossil collectors. It is often the rocks above and below the coal seams that have the best preserved fossils. Do remember that much material came out of mines, which are today closed and should never be accessed. But there are areas where Carboniferous Coal Measures rocks appear at the surface. Do some research and look for sites where you are permitted access and can find out background information, and always be aware of health and safety.”

Jon Clatworthy, Curator of the Lapworth Museum of Geology, University of Birmingham

Coal Measures Forest, Lapworth Museum of Geology, Winterbourne House and Garden, Digging for Dirt

Coal Measures Forest, giant clubmoss and horsetail, Lapworth Museum of Geology

These humid conditions proved perfect for the proliferation of ancient spore-bearing plants whose sperm travelled through the moisture trapped on the surface of leaves, in search of a reciprocal egg. Of course, abundant light, heat and water meant that many of these plants grew rapidly, achieving great mass in only a short period of time. One consequence of such exorbitant growth was that many plants became brittle and in the absence of woody tissue, often broke and fell into the murky water of the swamps below. Here, the exclusion of oxygen precluded the kind of decomposition which would ordinarily occur in the open air. As the earth’s surface became drier, these swamps gradually disappeared and were replaced by an enormous weight of soil. The previously preserved plants, under extreme heat and pressure, became first peat and eventually coal, as ever more water was lost, purifying the carbon content of the organic matter left behind.

The Carboniferous coal swamp may have looked and felt something like a tropical rainforest but the plants within it bore greater resemblance to many of those which grow closer to home. Fossil records show that the Carboniferous landscape was dominated by a giant clubmoss, Lepidodendron, growing over 30 metres tall, which produced a branching head and reproductive spores only once mature. This last minute reproductive gasp allowed the clubmoss to retain a slender figure for the majority of its life and grow in huge stands extremely close together sharing a single hectare with as many as 2,000 others. Beneath the giant clubmoss grew great tree-like horsetails, such as Calamites, which often achieved heights in excess of 10 metres, unattainable to its living herbaceous relatives, Equisetum. Both Equisetum and the now extinct Calamites produce distinctive whorls of leaves on brittle stems with hollow cavities which also made them vulnerable to collapse. Like the clubmosses, horsetails reproduce by spores. However, their persistence is better explained by a gigantic rhizomatous root which can also produce extensive clonal offspring when necessary.

Horsetail leaves, Lapworth Museum of Geology, Winterbourne House and Garden, Digging for Dirt

Horsetail leaves, Lapworth Museum of Geology

“There are probably a number of reasons why there are such big discrepancies between the size of Carboniferous plants and their modern garden relatives, including higher oxygen levels and the availability of space. Looking to the future, the study of fossilised plants can tell us which types of plants are adaptable and more resistant to climatic change, such as horsetails.”

Jon Clatworthy, Curator of the Lapworth Museum of Geology, University of Birmingham

Fossilized specimens of giant clubmoss and horsetail trees serve to underline the staggering diversity of plants and their intrinsic relationship with the environment in which they grow. Many of those species so imposing in the Carboniferous period failed to survive the Permian period which followed, when the earth’s surface became much hotter and drier to their detriment. Although many species were lost, this decline is not considered a mass extinction event, where the majority of living species become extinct, usually over a period of thousands of years, followed by several million years of extremely low diversity.  This diversity is the most important base layer in the complex pyramid of life on earth. Without plants to provide food and habitat, the many mammals, birds and amphibians with whom they coexist would simply perish.

“Carboniferous plants were not wiped out by a mass extinction, environmental change meant that many of the coal measure forests disappeared, but it wasn’t a major extinction event as we see at other times in the geological record.  The next one who knows – will it result from human activity or something else?”

Jon Clatworthy, Curator of the Lapworth Museum of Geology, University of Birmingham

Species extinction is an inevitable consequence of evolutionary churn as natural selection discards those less able to adapt. However, the effects of human interference are devastating. For much of our own history modern plants have existed in near perfect equilibrium, producing clean oxygen for us to breathe and locking billions of tons of carbon into organic compounds such as forests, oceans and fossil fuels. Burning these fossil fuels, such as coal, results in a greater percentage of carbon dioxide in the atmosphere which then traps heat and warms the planet. The current extinction rate is 1,000 times higher than the usual background rate. This extinction crisis is exacerbated as the practice of burning fossil fuels on an industrial scale continues to accelerate species decline and the once great coal forests of the past are plundered at the expense of those of the future.

Botanical gardens such as Winterbourne have an important role to play safeguarding biodiversity in cultivation. Over 6 million plants are grown in botanical gardens worldwide and some of these species survive in cultivation only, with no known wild populations. Whilst ecological restoration of wild habitats must remain a priority for the wider conservation movement, botanical gardens are also able to move and inspire local communities through the ex-situ collections they hold. Armed with the knowledge of their history, the living relatives of prehistoric plants provide not only a window into the ancient past of our planet but a means by which we can orientate our own place within it.

Come and see for yourself and find out more about the local industry and technology powered by plants. The Lapworth Museum of Geology is located only moments away from Winterbourne at the heart of the University of Birmingham’s Edgbaston Campus, so there’s no excuse for declining a spot of prehistoric plant hunting.

4 Thoughts on Powered by Plants

  1. Oddment


    What a vast history in your illustrations! And what a story to think about as we tread the earth and leave our footprints. I must add that I particularly liked the phrase “evolutionary churn” — it certainly is that. Thank you!

  2. Annie


    I’m always amazed when I come across these living fossils… club mosses or horsetail… on trails where I walk. Wonderful survivors! The practice of mountain top removal by coal companies has ruined great areas, the mountains along with streams and rivers in America. Thank goodness for botanical gardens like yours!

    • Winterbourne House and Garden


      Hello Annie, thank you very much – glad to be of service! It certainly puts things into perspective imagining some of our common garden plants and their relatives as enormous wobbly trees millions of years ago. We have a serious horsetail population in our Sandstone Rock Garden and learning about their history has given us a whole new appreciation of their ability to stick around!

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