Not all trees thrive in wet ground, but some species have adapted remarkably well to life with their roots submerged or in saturated soil. Among the best known are alder (Alnus), willow (Salix), and bald cypress (Taxodium distichum). Each plays a key role in stabilizing waterways, reproducing in wet conditions, and providing ecological benefits that extend to both humans and wildlife. Bank Stabilization Waterways are naturally dynamic systems, with banks that can shift and erode over time. Trees such as alder and willow are crucial in holding these banks together. Alders develop dense root systems that grip soil tightly, reducing erosion along rivers and streams. Similarly, willows have long, fibrous roots that spread widely and bind soil particles, acting almost like a living net. Bald cypress trees are less common along fast-moving rivers but dominate in swamps and floodplains. Their root systems, which include distinctive “knees” that protrude above water, help anchor them in soft, shifting sediments. In each case, the presence of these trees prevents soil loss and maintains more stable aquatic habitats. [embed]https://youtube.com/shorts/Tx6ra0WbrQ4?feature=share[/embed] Reproduction Through Water These species have also adapted to use water as a mechanism for reproduction. Willows are particularly effective at vegetative reproduction: broken branches can float downstream, take root in wet ground, and grow into new trees. Alders disperse lightweight seeds that are carried by water, enabling them to colonize new wet areas quickly. Bald cypress trees produce woody cones that release seeds into standing water, where they can establish when conditions are right. These strategies ensure that populations remain resilient in environments that frequently flood or shift. [embed]https://youtube.com/shorts/Hxf88-V27EY?si=JCGZWVBu7D7G1U0i[/embed] Benefits of Water-Resistant Trees Water-tolerant trees provide numerous benefits to ecosystems and people. By stabilizing soil, they reduce sediment entering rivers, which improves water quality. They also mitigate flood impacts: dense stands of willow or cypress can slow water flow, reducing the severity of downstream flooding. Their shade lowers water temperature, which benefits aquatic species such as trout and amphibians. In addition, these trees contribute to biodiversity by offering habitat and food for insects, birds, and mammals. [embed]https://youtube.com/shorts/KtqFq1FdOjA?feature=share[/embed] For human communities, the presence of water-resistant trees translates into natural flood control, cleaner waterways, and protection of infrastructure built near rivers and wetlands. In a time of increasing climate variability, species that withstand flooding are especially valuable as buffers against extreme weather events. Conclusion Alder, willow, and bald cypress are excellent examples of trees that thrive with their “toes in the water.” They stabilize banks, reproduce effectively in wet habitats, and deliver ecological services that benefit both nature and people. Preserving and planting these species where appropriate is an important step in maintaining resilient waterways and healthy ecosystems.

A woodland bank can refer to various structures but usually it refers to a raised earth structure found in a woodland or on the edge of a woodland.  Such banks are usually man-made, though banks can be natural formations. Sometimes, besides the bank there is a ditch, formed where the soil for the bank was excavated.  Banks may date back hundreds of years, possibly even to mediaeval times.  They are found in the U.K and Europe.   Such banks were created to Contain deer or livestock or Mark the boundary of an area of land Woodland banks may support ancient woodland species, such as dog’s mercury, bluebells and wood anemone.  Indeed, they can be biodiversity hotspots, or corridors that help the spread of species.  In some parts of the country, there are ‘hedgebanks’,  these are raised banks which support trees and shrubs on their top surfaces.  Over the years, these may have become field boundaries. Some of the UK’s best known woodlands contain banks, for example, Epping Forest, where the banks delineate old coppicing and former deer / livestock enclosures.  The area was managed by the Royal Foresters.  Wytham Wood is probably the most intensively studied wood in the country as it is owned by the university of Oxford and used for long term ecological research.  It has several wood banks (that support indicator species) with ditches that date back to mediaeval times.  Banks and ditches are also found in Sherwood Forest, which were used to ‘control’ deer in the royal hunting ground. [caption id="attachment_42471" align="aligncenter" width="675"] Woodland ban with mature trees.[/caption] If you wish to investigate woodland banks further, there some digital resources that might be useful - for example The Magic map at DEFRA.   This can many different different features of the landscape e.g. historic boundaries, designated ancient woodland, land use etc. You zoom into your area of interest, and then make use of different layers superimposed on the detailed map of the U.K.  https://magic.defra.gov.uk/home.htm The Ancient Tree Inventory, organised by the woodland trust.  Again, this is an interactive map of ancient and veteran trees.  Woodland banks and ancient trees often ‘coincide’ as trees often marked boundaries / divisions.    https://ati.woodlandtrust.org.uk Thanks to Stuart for images. Stuart is woodlands.co.uk manager for Devon. He holds a degree in Environmental Protection and is passionate about woodlands. He enjoys the hands-on approach that working with Woodlands.co.uk affords him, clearing tracks, putting up gates and fences and getting people started with their woodland. Stuart teaches conservation to NVQ level and is very involved in practical conservation work, carrying out bat surveys, dormouse surveys and building artificial badger sets.  

Sitka Spruce is a large conifer, it can grow to a height of 100 metres or circa three hundred feet.   Its trunk can be 5 metres (16 feet) in diameter.  Its size is comparable to some of the Redwoods.   It is native to the west coast of North America.  Its name Sitka comes from an Alaskan community where it is widespread, though it can be found all along the west coast of Canada and the United States.   Loggimg has reduced much of the native spruce forest, particularly of the larger trees.   The spruce is a long lived tree, some estimated to have an age of 500 years or more.  Size in itself is not necessarily an indication of age as a tree can grow rapidly in the right conditions, adding up to a cubic metre of wood in a year.  The bark of the tree is ‘scaly’ and tends to flake off.  The deeper, inner bark has a reddish brown colour.  The leaves are needle like and stiff, somewhat flattened in cross section with a blue green colour.  The root system is relatively shallow, with long lateral roots, which means it can be susceptible to ‘wind throw’. Sitka ‘prefers’ soil high in calcium and magnesium (magnesium is essential for chlorophyll formation).  Its wind dispersed seeds readily colonise areas cleared by fire or exposed by land slip, acting as a pioneer species but in coastal areas it is a dominant, climax species. Because of its rapid growth rate and the nature of its wood, it is valued as a source of timber and used in paper production.  Specialist uses include the making of musical instruments (pianos, harps) because of its resonant nature.  It was introduced to the UK in the nineteenth century by David Douglas - the botanist after whom the Douglas Fir is named.   Sitka Spruce now accounts for some 25% of forest / plantation cover in the UK.  As with any monoculture, the biodiversity in plantations is limited and there is a move to change this.  Diversification helps make such forests more resilient to new pests and pathogens, and also climate change. Some 500+ species use Sitka trees as a space for living or for feeding, when viewed across the UK.   Most of these species are not specialists unique to Sitka and are found on a wide range of other trees.  Research is underway to use broad leaved trees to help diversify Sitka forests.   The introduction of such trees might improve litter decomposition and nutrient cycling.   A number of trees are possible candidates e,g. oak, birch, beech, spruce and pine.  They would help support existing species visiting Sitka and add others.  However,  individual trees of these tree species will not grow long-term in stands of Sitka. However, it might be possible to achieve the benefits of diversification by using small blocks of single species within specific management areas.  More research is needed to determine the optimal size and spatial arrangement of such blocks. [caption id="attachment_42460" align="aligncenter" width="675"] Sitka spruce[/caption] Further reading : https://academic.oup.com/forestry/advance-article-abstract/doi/10.1093/forestry/cpaf040/8203130?redirectedFrom=fulltext t

When thinking of conifers, one might feel a bit ‘schizophrenic’.  Perhaps picturing a Leylandii encroaching on your garden, whilst also remembering your Christmas tree.  Maybe the typical image of conifers is that of a tree with dark green foliage all year round.  However, this would be something of a disservice to the Conifer family - the Pinophyta, which contains an amazing variety of trees, many of which are at risk of extinction.  This group includes cedars, firs, cypresses, junipers, larches, pines, hemlocks, redwoods, spruces, and yews. [caption id="attachment_32107" align="aligncenter" width="650"] Leaves on the branchlets of Dawn Redwood[/caption] Conifers are important because They dominate vast areas of land, particularly in the Northern Hemisphere,  forming the boreal forests or taiga. Softwood from conifers accounts for approximately 45% of global timber production. Pine, spruce and larch are often grown specifically for softwood production. The wood is also used in the paper production[.and, to a lesser extent, in making plastic from chemically treated wood pulp].  Some species produce edible seeds , such as pine nuts provide foods such as pine nuts for humans and wildlife and juniper berries, which are used to flavour gin.  The Monkey Puzzle tree, (also known as the Pehuen Pine, native to Chile and Argentina) produces seeds known as piñones; traditionally harvested by indigenous communities.  [caption id="attachment_27592" align="aligncenter" width="600"] Monkey puzzle tree[/caption] To see the diversity of the Conifer family one could visit the Bedgebury Pinetum.  This is home to one of the world’s most important conifer collections.  Bedgebury was established in 1925 by Kew Gardens and the Forestry Commission.  The curator at Kew had observed that the conifers there were ‘being choked by London Smogs’.  The site at Bedgebury, situated on the Southern Kentish weald, was ideal.  It offered an escape from the pollution of London and it had wet and free draining areas, plus varied soils so it a range of conifer could be grown. The land already had some conifers that had been planted by Viscount Beresford - an evergreen enthusiast.  In 1925, some 315 trees were planted.  This year, to celebrate reaching a century, some 89 of the original trees are marked with special yellow labels.  For  its first twenty years, the pinetum was managed by William Dallimore. His diaries record in some detail the trees he planted, and the challenges faced in establishing the pinetumIf you visit, then you might walk through through Dallimore Valley, and view his legacy. Bedgebury soon became a centre for the scientific interest in conifers, their conservation, and landscape planning.  The current curator is Dan Luscombe. Apart from seeing a range of conifers, the pinetum offers a variety of activities, e.g. family cycling, mountain biking and walking, There is also the play trail or you can explore the canopy on a Go Ape tree-top adventure or challenge.  It is rumoured that the Gruffalow lurks within the grounds of the  Pinetum. There is also a cafe, serving a range of drinks, plus  breakfast and lunch options. The pinetum is open from from 8 AM to 8 PM (March 2025 to 26 October 2025), and there are charges for car parking.  

In parts of the South West,  there is open moorland but some of its features betray its history.  Running across the landscape there are faint lines.  These lines are reaves, and they are a legacy of ancient farming and land management technique.  They may run for many miles across the countryside.  Reaves were essentially walls constructed from local stone and earth, and may date back to the Bronze Age.  They were used to divide up the land for farming or grazing by livestock.     Instead of creating hedgerows, walls were built probably due to the availability of the stone [granite / slate] and the harsher climate back then. The reaves allow archaeologists some insight into the nature of ancient societies, their land use and agriculture. The area of Dartmoor and its environs offer a well preserved historic landscape {eg. The Great Western Reave) that has not been heavily ‘over-written’ by subsequent development.   In medieval times or later, hedgerows were planted along or near many of the reaves. Whilst reaves were not originally built to support hedges they sometimes became the base for hedgerows enclosing parcels of land.  Some reaves align with more recent earth banks that are topped with shrubs of hazel and hawthorn.  Many reaves have been gradually colonised over the years by various plants and animals.  The structure / integrity of some reaves has been lost as their stones / slates were ‘redeployed’ to build new dry stone walls / boundaries in the 18th and 19th centuries. Another type of boundary is the cornditch, This a bank with vertical stones on the side. Sometimes there is also an actual ditch - created where the soil was excavated to build the bank.  Cornditches separated common grazing land [open moorland] from enclosed land / fields, essentially they stopped livestock entering cultivated areas.  They may be seen around Exmoor and Dartmoor. Reaves, hedgerows, hedges, banks all serve to separate up parcels of land, but they also add character to our countryside and serve to provide continuity across the landscape for many species (plant and animal) to move around. [caption id="attachment_42471" align="aligncenter" width="675"] Woodland bank with mature trees.[/caption] Many hedges have been lost due to the expansion of agriculture and increasing urbanisation, others have fallen into disrepair and some are flailed within an ’inch of their life’. [caption id="attachment_25527" align="aligncenter" width="600"] A flailed hedge[/caption] A sustainable way of managing tree lined hedge banks and a better alternative to the excessive cutting with heavy machinery is the traditional crafty of hedgelaying. This technique involves partially cutting stems of shrubs at a diagonal angle know as ‘pleaching’. Traditionally this would have been done with hand tools such as billhooks and axes with different regions of the Country having different designs of tool. Most species can be laid but most common are shrubs like hazel, hawthorn and blackthorn with some trees such as oak, beech or birch being allowed to grow on to become mature trees known as ‘standards’. Shrubs are laid by bending over and weaving them together holding with ‘stogs’ (see the woodlands blog on How to lay a hedge).  Skilled workers declined in the later part of the 20th Century but is now on the rise again thanks to changes in land management aims and some grant funding being available. Ideally a hedge should be laid within 10 years of planting and should be and then can be regularly trimmed. After 50 years the hedge can be laid again. Some hedges, such as beech lined stone-faced hedges are not traditionally laid but trees are pollarded (cut to a height above where regrowth can be eaten by livestock or deer) on a rotation to prevent trees becoming too heavy and blowing over in the wind. This is also a good supply of timber for logs. Hedges act as biological corridors, and provide unique habitats / niches.  Even dry stone walls offer opportunities for lichens and mosses, leading to the formation of biocrusts. Hedgerows are home to some 600 different plants, 1,500 insects, 65 birds and 20 mammal species – offering food and shelter, breeding and nesting sites. Many of these species have been identified as vulnerable. The loss of hedgerows, or a decline in their quality and care would effect the populations of these species.  Hedgerows also serve to capture carbon, absorbing CO2 from the atmosphere which helps fight global warming by storing carbon in complex organic compounds.  The roots of hedgerow shrubs and trees help reduce soil erosion, stabilising the soil and improving drainage, whilst the above ground stems and leaves reduce wind speed. In towns and cities, the leaves and aerial parts of hedges can ‘catch’ roadside pollutants and particulates. Thanks to Stuart Brooking, who is the woodlands manager for Devon.

Ash dieback began to spread in Europe in the 1990’s, reaching England in 2012.  It is a fungal disease that slowly but surely interrupts a tree’s ability to transport water.   The fungus responsible is Hymenoscyphus fraxineus, which is native to Asia.  The death / loss of mature trees not only reduces carbon dioxide uptake but also represents the loss of habitats for many species of insects and other animals.  The dead trees are also a hazard to people and property. Though many ash trees have now died after infection with this fungus, there is a small glimmer of hope on the horizon.  Some British ash trees are evolving a degree of resistance to the fungus.  Scientists from Kew and Queen Mary University of London have studied the genetic makeup of many mature european ash trees, and also hundreds of young saplings (at Marden Park in Surrey).   This revealed that resistance was more commonly found in young trees - a shift in the genetics of the trees within a generation.   The resistance to the fungus is NOT complete, but if these young trees make it to reproductive maturity then there will another chance for natural selection to ‘refine ‘ the process, through their offspring. However, it may be that a careful breeding program will be needed to establish true resistance / immunity. Interestingly, ash dieback has not reached America but the emerald ash borer has.  This insect is spreading and killing trees.  It is another example of the effects of the globalisation of world trade. Insects and other animals from across the world are being ‘mixed up’, moved from their native regions to new areas where they spread and cause damage as their predators and / or parasites have not travelled with them.   Trees and shrubs are now facing challenges and threats at an unprecedented rate. see also :  https://www.qmul.ac.uk/media/news/2025/science-and-engineering/se/british-ash-woodland-is-evolving-resistance-to-ash-dieback-.html  

JAcross Europe, the red squirrel is recognised as an endangered species.  The U.K populations are at risk due due to :- Habitat loss Competition with Grey Squirrels The effects of the squirrel pox virus The last two are a result of the introduction of the grey squirrel from America in the 19th century. Red squirrels are at home in all types of woodland and may even be seen in parks and gardens, but they 'like' mixed conifer forests best.  Scotland is home to many of the U.K's red squirrels. The number of squirrels is quite small – estimates of their number vary, perhaps there are less than 300,000* across the whole of Britain.   The status of red squirrel populations is a matter of considerable interest. [caption id="attachment_42416" align="alignleft" width="300"] Screenshot[/caption]  In 2014, it was noticed that some members of the Scottish red squirrel populations had abnormal growths on their ears, snout and limbs. Further investigations found that the squirrels were suffering from leprosy.  Leprosy  is a bacterial infection,  caused by two different species of mycobacteria: Mycobacterium leprae and Mycobacterium lepromatosis.   The two types of  bacteria have slightly different distributions in the squirrel populations of the U.K.  Whilst leprosy in squirrels was first reported in 2014,  it is likely that the disease has been around in squirrel populations for much, much longer, probably hundreds of years. Profesor Verena Schünemann,  Christian Urban et al have studied bacterial DNA extracted from human skeletons, dating from 400 CE to 1400 CE with deformities associated with leprosy.   They 'reconstructed' the genetic makeup of mediaeval forms of the bacterium.  Leprosy was not uncommon across Europe in mediaeval times - indeed up to the sixteenth century.   Disease, in its many forms , was a common part of life -  dysentery, diphtheria, typhoid, smallpox, and plague meant that life expectancy was limited. The last indigenous case of leprosy in the UK dates back to 1798.  In humans, leprosy causes muscle and nerve damage, which lead to deformity, blindness and disability.   Interestingly, research by Dr. Sarah Inskip has revealed that a pre-Norman skull [found in Hoxne in Suffolk] had a leprosy strain related to a form known to affect squirrels.  The same strain has also been found in medieval scandinavian skeletons.  It is possible that the  trade in squirrel pelts (and meat) could have contributed to the spread of the disease. Strong trade connections with Denmark and Sweden were in full flow in the medieval period.  Squirrel fur was also used as a lining for fine clothes and squirrels were kept as pets by some. The historical spread of leprosy is not fully understood.  The disease may have passed from squirrels to humans or vice versa in historical times.  Further study of the microbes that cause this disease (and that in squirrels) will help determine how the disease is acquired and transmitted.    The risk to human health is low. (Even so, good hygiene should be followed during any contact with wild animals). Professor Anna Meredith  (University of Edinburgh) is researching into this disease in squirrels.   Further reading / articles: https://www.newscientist.com/article/mg14819991-200-virus-blamed-on-invading-squirrels/ https://www.science.org/doi/10.1126/science.aah3783 https://www.theguardian.com/science/2017/oct/25/medieval-love-of-squirrel-fur-may-have-helped-spread-leprosy-study-reveals https://www.sciencedaily.com/releases/2017/10/171025103109.htm

Forests across Europe occupy some 40% of the land area, and until recently they were regarded as not only a source of timber but also an important ’sink’ of carbon.  That is to say, they took in more carbon dioxide in photosynthesis (and stored it away in complex organic compounds) than they released in respiration. However, in recent times, these important biomes have turned from carbon sink to carbon source.  This year, the Finnish forests changed from sink to source.  Forests in the Czech Republic and Germany also released more carbon than they absorbed.  Though French forests are still a sink, their absorption of carbon dioxide has roughly halved in recent years (from 74 million tonnes of CO2 to 37.8 million tonnes in 2022).   Norway has seen a similar reduction in carbon dioxide storage from 32 million tonnes to 18 million tonnes. Seemingly, forests across the continent are losing the ability to act as carbon sinks, but why?  One reason seems to be the increased harvesting of timber,  many forests are privately owned and run on a commercial basis.  The Russian invasion of Ukraine has been a factor as sanctions against Russian timber has lead to more ‘domestic’ culling, for example in Finland.  However, climate change is an important factor in this downturn.  In recent times, droughts (in 2018 and 2022) have had a significant effect of forests, trees are stressed and the effects of drought have been greater than anticipated.  Drought can also be coupled with other extreme weather events (such as storm damage) and outbreaks of bark beetle (which have particularly affected spruce woodlands).  The Czech Republic has reported several outbreaks of bark beetle in recent times. What can be done to mitigate this loss of carbon sinks? Clearly reducing the harvesting of trees for timber and the banning of clear felling would help.  After a clear cut in a boreal or temperate region, it can take a forest 10 to 15 years to become a sink again, and even longer for the original emissions associated with the clear cut to be compensated for. Increasing the diversity and resilience of trees used in forestry is another approach to increasing CO2 absorption, however, it would take some time to determine which trees would be most effective in creating a carbon sink in the face of climate change.  Sadly, it is also the case that many tropical forests are in decline in terms of carbon storage due to deforestation,  expansion of agriculture and fires. Further reading : https://forest.eea.europa.eu/topics/forest-and-climate/carbon-sinks-and-sources