Blog - Energy, sustainability & economics
Last tree standing ?
Just as many animal species are threatened with extinction, so are many species of tree. In fact, one estimate suggests that up to a third of tree species are under threat - that is more than 17,000 species. This equates to more that the number of endangered mammals, birds, reptiles and amphibians put together. In 2021, the IUCN (the International Union for the Conservation of Nature) produced a report on some 58,497 tree species which identified 17,510 species as being threatened (and 142 extinct in the wild). In Mauritius, some 57% of tree species are at risk of extinction! Ideally, no single tree species should be lost, a single species can be an integral part of an ecological network. Its loss could result in the disappearance of many species and even an ecosystem collapse. Some tree species are now represented by single numbers of specimens. The ‘lonesome palm’ (Hyophorbe amaricaulis) is probably the last surviving member of its species. It is to be found in a botanic garden in Mauritius. It is an old, damaged and spindly specimen. It has problems with fruit formation; each of its fruits contains but one seed and the seeds are difficult to germinate (even the botanists at Kew could not persuade them to grow). The best approach to saving vulnerable trees is to protect their natural habitats. This might mean controlling grazing by herbivores, or banning logging in sensitive areas. Sometimes a change in cultivation techniques can make a difference. The Lansan Tree produces a valuable, aromatic resin. It is endemic to the Windward Islands and its fleshy fruits provide for native pigeons and other wildlife. The resin is collected (tapped) from the tree by slashing the bark every one-to-two weeks. However, over-tapping for the resin can lead to the trees becoming infected with pathogens, then rotting, or subject to termite attack. The pathogens may spread to untapped trees. Unregulated tapping and conversion of land from rainforest to agriculture have led to Lansan Tree populations all but disappearing in places. On Saint Lucia, where there is a large but threatened population of Lansan Trees, there is hope after the introduction of a sustainable resin harvesting technique. This technique does not damage the tree but still allows a good yield of the resin. This, coupled with training of licensed resin tappers should protect the trees. Some species have reduced populations because their pollinators have been lost, so fruit and seed production has ceased. Other species have separate male and female plants (dioecism) and the small populations that remain are represented by only one sex. This was true for the catkin yew population in Hong Kong, where all the trees were males. A global search found a female specimen in the Royal Botanic Garden in Edinburgh. Cuttings from the Edinburgh tree have now been planted in a managed site in Hong Kong. Hopefully when they flower, fruit and seed production will occur; but it may be a long wait for the young trees to reach sexual maturity. Another species, the oleander podocarp (Podocarpus neriifolius) has been nursed back to viability by similar techniques. Some rare and isolated trees produce seeds but getting them to germinate is another matter. Many seeds enter a state of dormancy and have extremely specific requirements for them to germinate and grow on. In many cases, their needs are simply not known. The seeds may need a particular temperature regime, or exposure to cold, fire, smoke or light of a particular wavelength. Some seeds may need to travel through the gut of a particular animal before they will germinate. Sometimes, scientists have used to embryo culture. The embryonic radicle (root) and plumule (shoot) is extracted from a seed and then grown in a sterile nutrient culture medium. This technique was used at Kew with the ‘lonesome palm’ as attempts to grow its seeds had failed. Embryo culture resulted in plantlets forming but after a while their roots turned brown and the young plants died. There are success stories. A Cypress species Widdringtonia whytei, was reduced to a few trees in Malawi, as a result of illegal logging for timber. Many seedlings have been planted on Mount Mulanje and a good number of these have survived. [caption id="attachment_25196" align="aligncenter" width="675"] Entrance to the Millennium Seed Bank[/caption] When and where seeds are actually available, they can be dried or frozen (cryopreservation) and placed in seed banks, for example the Millennium Seed Bank at Wakehurst Place. We have to hope that through various interventions, the use of seed banks, botanic gardens and arboreta that we will be able to save many rare and threatened tree species, you never know when one might be needed.
From meadow to woodland.
Anyone who has worked with us at Hive Cleaning, knows that sustainability is one of our most important guiding principles, along with being an ethical employer and exceptional cleaning standards. We take sustainability ambitions seriously and have reduced our direct emissions to zero and are on track to reach Net Zero in 2025. However, we didn’t want to just focus on our day to day operations (being technically ‘green’) but wanted a direct involvement with nature and natural ecosystems; that’s how our idea of a reforestation project was born. We fell in love with a meadow (near Clovelly, in North Devon), a beautiful part of the world. The meadow has stunning views and we could immediately imagine how tree planting in the meadow could further enhance the biodiversity and beauty of the area. [caption id="attachment_40611" align="aligncenter" width="675"] Hive Wood Sign[/caption] We have renamed Rosedawn Meadow to Hive Wood, and we are planning to plant over eight thousand trees over the next 15 years. As a part of our wider ESG strategy (this documents the company's impact on the environment) , we are committed to : ● Recreate historic hedgerows around the boundary ● Only planting local native broadleaf tree species ● Measuring the sequestered carbon via Carbon Trust ● Never selling the carbon credits ● Never felling the trees (except where necessary in terms of managing the wood) ● Improving biodiversity and creating a haven for flora & fauna ● Using Hive Wood to promote biodiversity and carbon reduction / sequestration. We started the planting the trees and the hedgerow in March, this year. So far, we have planted eight native species: sycamore, rowan, white poplar, sessile oak, buckthorn, black alder, blackthorn and hornbeam.
Sweet chestnut finger-jointing at InWood in Whitesmith,East Sussex.
Chestnut coppice grows in abundance in the South East of England, especially in Kent and East Sussex. However it is quite small diameter, being harvested about every 15-25 years. The timber is very strong and resistant to rot. For some uses it is better than oak and unlike softwoods it does not need treating with chemicals. The problem is how to turn these relatively thin stems into useable pieces of timber and a small company, InWood, has found an answer. I was visiting The Woodland Centre to collect a batch of six-inch decking that the factory team had made for me, and they offered me a tour round the factory. Their answer is to glue it together using finger-joints which are actually stronger than the wood itself and you can use it for decking, cladding and even structural beams. My decking boards had machined-in grooves to stop it being slippery and there were other options for width such as their three-inch or four-inch boards. Peter Black, the factory manager, explained how they buy sweet chestnut planks and process them by sawing them to width, taking out the knots and any wood that is rotten or infested with woodworm. He says that there are also occasional shotgun pellets which need removing - many of the chestnut coppice woodlands in East Sussex are used for pheasant shoots. The sawing produces short pieces of the same width and thickness but the highlight for the visitor is seeing their German machine which automatically cuts a tooth-like pattern in each end and puts polyurethane glue on it. These sections are then pushed together to make long, virtually defect-free planks. The factory generates plenty of waste wood which burns well and burns hot - it is either used for heating the workshop or sold for firewood. Enviously I looked at the part of the workshop where they use a huge hydraulic press to make “Gluelam”, being laminated beams from planks. These bigger timber beams have lots of advantages over the alternative of using large sections of tree trunk: the wood is much more stable, is less likely to twist & warp, longer sections can be made and there is often less wastage. InWood’s front man is Alan Ellis whose phone number is 01825 872550, and he is happy to supply trade or retail. On their website (www.in-wood.co.uk) you can find some spectacular garden rooms which they make from laminated chestnut. We got our Sweet Chestnut decking from InWood because of the quality, and their sensible prices. This method of producing timber supports sustainable British Forestry as well as the coppicers. Successive generations of coppice workers have used their skills since at least Roman times, when sweet chestnut was first introduced to southern England.
The DiversiTree Project and Woodland Diversity
Rapid onset climate change, and the spread of new pests and diseases are creating unprecedented challenges to the long-term survivability of UK woodlands. This looming threat is becoming ever more tangible, and the need for strategies of resilience building is urgent. Promoting diversification within and amongst woodlands has been identified as one such strategy with the potential for significant, positive impact. DiversiTree is a UKRI-funded project led by the James Hutton Institute which is measuring the impact a more diverse mixture of tree species has on building resilient woodland ecosystems, as well as how woodland managers and others understand woodland diversity, and what they are CURRENTLY doing to promote resilient woodlands. The project also hopes to generate practical advice and results which managers can use to make better informed decisions regarding the species mix of their woodlands, especially with regard to conifers. A key question which often accompanies discussions of woodland diversity is the planting of non-native species within British woodlands. The DiversiTree project is taking an evidence-focussed approach to its assessment and are investigating how ecological resilience interacts with woodlands with different priorities or objectives and what this might mean for the longer-term ecological sustainability of the forests of the UK. In actuality, many native woodlands are rather species poor, and could potentially benefit from a period of managed diversification with native species, non-natives, or a mixture depending on local objectives and context. What is critical here, is understanding the ecological role ANY tree can serve in a complex landscape, and planting in a manner which enhances and strengthens a woodland’s biodiversity. If you’d like to learn more about our work and keep updated with our progress, please follow us on Twitter @DiversiTree_UK (https://twitter.com/DiversiTree_UK?s=20) or email [email protected] with any questions. Seumas Bates (Environmental Anthropologist, Bangor University)
New uses for ‘waste’ plant material.
Many trees emit a scent or fragrance. They form volatile organic compounds (VOC’s), often oils. Pine trees, for example, release pinenes. Such VOC’s contribute to the smell that you may experience as you walk through a woodland. The VOCs contribute to the formation of aerosols. An aerosol is a ‘mixture’ of very small particles (solid or liquid) in air; other examples of aerosols include mist, cigarette smoke, or even car exhaust fumes! Recent research by the University of East Finland has showed that aerosols formed from VOCs can reduce the amount of solar radiation that reaches the earth’ surface, by scattering some of the radiation back into space. [caption id="attachment_40200" align="aligncenter" width="532"] Felling in progress[/caption] Pine trees are often grown in vast numbers and periodically felled for timber and paper making. One by-product of paper-making (by the Kraft process) is turpentine - formed by the condensation and collection of the volatile oils in the wood). The pinenes (α and β) are major constituents of turpentine. ‘Turps’ is used as a solvent to thin oil-based paints, for producing varnishes and as a ‘raw material’ in the chemical industry. α-Pinene was used to make toxaphene (an insecticide, now banned). Pinene can also treated with acetic acid to make a perfume with a pine needle smell. Recently a team of scientists at the University of Bath have found a new use for the by-products of paper production. Using pinene from turpentine, they have been able to make a number of pharmaceutical compounds that can then be made into the painkillers - paracetamol and ibuprofen. They have also successfully made other chemicals from the plant based turpentine, including compounds that may be used to synthesise `beta-blockers (heart tablets) and salbutamol (used for asthma). At present, many pharmaceuticals and other chemicals are ultimately derived from crude oil. Hopefully, this research will ultimately lead to a more sustainable and ‘green’ approach to drug / pharmaceutical manufacture. Biochar is the black residue, consisting of carbon and ashes that remain when plant biomass is subject to pyrolysis - that is, very high temperatures with very little or no oxygen present oxygen. The material that remains is largely elemental carbon. The benefits of converting plant biomass into biochar is that the carbon is ‘locked up’, rather than being released by decay and decomposition into the atmosphere as carbon dioxide. Its advocates claim that when added to soil, it improves soil structure and function, as well as being a form of carbon sequestration.. [caption id="attachment_40215" align="alignleft" width="300"] cocoa fruit[/caption] Various forms of biomass (woody debris, corn stalks) have been used to produce biochar, however, a novel method makes use of ‘discarded’ cocoa bean shells. These are heated to a temperature in excess of 600oC, with no oxygen present. This particular form of biochar is being produced in in Hamburg. The plant, which is one of the largest in Europe, receives a supply of used cocoa shells viably a network of grey pipes from a neighbouring chocolate factory. Apart from its use as a fertiliser, it is possible that it might be used as an ingredient to create a ‘green’ (or more environmentally friendly) form of concrete. The sequestration of carbon is vital if we are to avoid the worst effects of climate change. Global warming has triggered an increase in heatwaves, floods, droughts, and forest fires in recent years; June temperature data confirms it was the planet's hottest on record. Cocoa fruit : courtesy of Pixabay.
Woodlands.co.uk was chosen as the sustainability sponsor for the February 2023 conference, State of Open 2023. Mostly held for those working in computing and data, this event was held at the QE2 centre in Westminster, with several hundred individuals who networked and learnt more about open source, open data and open standards. The highlight was the speech by Jimmy Wales, founder of Wikipedia, explaining that Wiki isn't just about free and open information but about structure: their whole model is unusually open. It's truly democratic amongst wikipedians and is the antithesis of top-down models which dominate most of the world's organisations. As sponsors, woodlands.co.uk committed to plant at least one tree for every conference delegate as a carbon-offsetting measure and to encourage biodiversity. It turns out that at this conference relatively little extra carbon was produced for various reasons - the QE2 conference centre itself has strong environmental policies and the delegates were mostly either UK-based or were travelling to Europe anyway for a related conference. Nethertheless many of them took away free eco-merchandise from the Woodlands stand, including seeds for planting and wooden pens. Lots of the conference attendees were also interested in buying land for tree-planting so that their company would be offsetting its own carbon footprint and the staff would have a nearby place to go and enjoy. Sustainability sponsors can occasionally be accused of offering 'greenwash" but in this case there was no risk of that because the OpenUK movement is already so committed to sustainability and to using software to reduce carbon emissions. And in this case, too, the sponsor was offering practical measures such as the planting of defined numbers of trees in the UK (in Kent) rather than a theoretical payment to a nebulous foreign project. Conference participants were offered the chance to take away seeds to plant their own oak, cherry, lime, chestnut or sycamore trees. The role of sustainability sponsors at conferences varies but can involve financial support or the promotion of sustainability initiatives. Some eco sponsors also offer energy audits, sustainability assessments or carbon footprint analysis. According to the AI chatbot, ChatGPT, "Overall, sustainability sponsors play a critical role in supporting the transition to a more sustainable future by providing resources, expertise, and advocacy to organisations working on sustainability issues."
woodlands web update – 22
Back to one’s roots? Some of the effects of agriculture are very obvious, such as the vast areas of land now covered by monocultures of wheat or oil seed rape. The expansion of mechanised agriculture has resulted in significant reductions in biodiversity, for example, through the loss of hedgerows and ponds (see the post on ghost ponds in Norfolk). However, agriculture has others effects that are not quite so obvious. Soils are ‘filled’ with roots, and roots help engineer landscapes. They help: break up bedrock, improve permeability of the soil to water stabilise the soil, store carbon transport water and minerals to the plants. They have been doing this for millions of years since the colonisation of land by plants. Now, research by scientists in the United States, has shown that the roots of agricultural crops are significantly less deep than those of the natural vegetation in an area. Indeed, the root depth may be shallower by some 60 cm, compared to the natural root systems of an area. If the soil is less root material then there is decreased carbon storage, reduced nutrient recycling and possibly reduced soil stability. Whilst there are some areas where “woody encroachment” is occurring (for example, shrubland taking over in some grasslands and forest advance into regions of tundra so root depth is increasing) - the onward march of agriculture is dominant. Full details of this analysis / research : https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022EF002897 Shrinking in winter Recent research has shown that some small mammals (like moles and shrews) shrink in size during periods of cold temperature. This shrinking is thought to be a response to cold temperature rather than lack of resources. This change in form has been known for some 70 years and is referred to as Dehnel’s phenomenon. Professor Dehnel observed this change in form in shrews [in Poland in 1949]. However, shrews have a short lifespan so an extended studied of this phenomenon with these animals was not / is not possible. Recent studies by German researchers have focused on moles, who can survive harsh winters by becoming smaller. It is thought that this reduction in size enables energy savings. According to Dr Dina Dechmann this reduction in size comes at a cost, as the animals’ cognitive behaviour is affected. Further information here : https://royalsocietypublishing.org/doi/10.1098/rsos.220652 Farming and sustainability With the expansion of farming, less and less of the land is available for our native plants and animals, Hedgerows and ponds have been lost / removed, natural habitats have been reduced. The government has produced new guidance on environmental land management schemes (ELMs). That is subsidies that will be paid to farmers if they help promote and protect nature and improve the environment (e.g. using less insecticide and reducing pollution). There would be payment /subsidies for some 280 measures, for example : Creating fenland from lowland peat Maintaining sphagnum moss Creating land that could produce organic fruit Establishing a skylark plot Adding organic matter to the soil Creating green cover over winter (on 70% of the land) Welcome as these measures might be, there is criticism that they favour big arable farmers and do not really help those working on more marginal land (such as upland and moorland regions). Further information available here. Trees - From Root to Leaf For those who like their trees, here is a new book about them. Written by Paul Smith -who was head of the Millennium Seed Bank of the Royal Botanic Garden, Kew. Not read or seen a copy but the Sunday Times comment "'Stunningly illustrated and detailed ... a celebration of all things arboreal, from the seeds, leaves, flowers and fruit to the diversity of trees and how they have influenced art, culture and science' suggests that it might interest. See "https://press.uchicago.edu/ucp/books/book/chicago/T/bo186012850.html"
Felling trees, planting trees.
In recent times, we have heard much about various initiatives to plant more trees, such as The Queen’s Green Canopy tree planting project to mark the platinum jubilee. Tree planting is part of the government’s plan to mitigate certain aspects of climate change as the trees will absorb carbon dioxide from the atmosphere, which is one of the principal greenhouse gases. Once absorbed and used in photosynthesis, much of this carbon is then locked away for many years in the form of complex compounds, such as cellulose and lignin. The peak of carbon dioxide uptake by UK woodlands and forests was estimated to be just under 20 million tonnes in 2009. However, since that time the amount has actually declined. Many of the conifer plantations that were planted back in the 1970’s and 1980’s have now been felled / harvested, so they no longer contribute to the uptake of carbon dioxide. It is important that these clear felled areas are replanted and tree cover restored; indeed, in places increased. Planting rates have risen in Scotland but the performance by the rest of the UK is somewhat limited. Even with new planting, it takes time for such new forests / woodlands to reach the CO2 absorption levels seen in the 2000’s. Continuous cover forestry (CCF) is a different approach to woodland forest management; it seeks to avoid clear felling and promotes a mosaic of trees by age and species. There are a number of factors that influence new planting, such as the availability of land. Using high grade agricultural land for tree planting would affect targets for increased agricultural productivity and domestic food supply. Also, with climate change and the increasing number of extreme weather events (storms, flooding, drought etc) greater thought needs to be given to risks such as forest fires. Recent months have demonstrated the ferocity of forest fires in France, California and Portugal. We cannot assume that the UK will be exempt from such events. Similarly, we have witnessed powerful storms (such as Storm Arwen) which felled many thousands of trees (and impacted on public services such as electricity and train travel). The warming climate is also associated with ‘new’ diseases and parasites in our woodlands and forests. New planting needs resilience ‘built in’ to the plan. The Environment, Food and Rural Affairs Committee in its recent report (2021/2) has made a number of important comments in relation to tree planting in the UK, notably : It noted that the Forestry Commission had said that nurseries in the UK will struggle to expand production to deliver the number of young trees required for the Government to achieve its planting ambitions. There is a lack of a sufficiently skilled and large workforce to achieve England’s tree planting ambitions. To meet the Government’s tree planting goals, the UK will need to import seeds and young trees (until domestic capacity increases); and this carries the risk of the introduction of pests and diseases.