Now that the trees have shed their leaves their branches are more clearly visible and this highlights the colour of some willow species. Beside Fonthill Lake, near the arch, are a few trees which catch the eye, as they shine orange in the afternoon sun. Elsewhere you might see willows with purple, yellow or red twigs. There are many willow (Salix) species and a huge number of varieties which have been bred for different purposes and their colour. Over the centuries, people have found numerous uses for willow and given it different names, such as osiers or withies.

In the past, chewing willow bark was used to relieve pain. Nowadays, the painkiller Aspirin is derived from salicin, a compound found in the bark of all Salix species. Baskets of all sizes have been made from willow all over the world for centuries and put to a multitude of uses. Willow was also used to make furniture, hurdles, lobster pots, cages, fish traps and, of course, cricket bats. Somerset is an important area for the production of willow, where hundreds of acres are dedicated to growing different varieties for varied uses.

The advent of plastics replaced many uses of woven willow - also known as wicker – but new uses continue to be found, for example sculptures large and small, and you can now even get a wicker coffin. The latest development is planting willow as short-rotation coppice, which can be mechanically harvested and used as a perennial bioenergy crop. This can use land less suited to food production and, because it regrows from the cut stool each year, doesn’t require annual planting.

Willows can be found throughout the country, especially the commonest, the goat willow, also known as pussy willow or great sallow. In common with all other willows, it is pollinated by insects and has male flowers on one tree and very different looking female flowers on another. In full bloom in spring, the catkins provide a huge, early source of nectar for insects. Their foliage also provides a food source for the larvae of several moths, as well as the wonderful Purple Emperor butterfly.

Willows are very prone to hybridise with other species of willow, which makes certain identification difficult. But it has resulted in a great variety of forms including the fabulous weeping willow. To confuse matters further, poplars which are closely related (but wind pollinated) also have catkins and alternate buds and leaves like willows. However, poplar leaves are triangular, or diamond shaped, while willows (apart from goat willow) are long and thin.

Although willows are relatively short-lived trees and not valued for their timber, they are nonetheless an important but easily overlooked element of our countryside, without which many other species would struggle.

​Andrew Graham

At this time of year hedges are looking at their best, as far as fruit is concerned. The winter storms and hedge cutting haven’t bashed it away, and the birds and animals haven’t started in earnest.

Following this summer’s wetter than normal weather, there is a good crop of rosehips, crab apples, and berries on blackthorn, spindle, hawthorn, wayfaring tree, guelder rose, rowan, elder and buckthorn. This (incomplete) list shows how important it is to plant a whole range of species when planting a hedge. Ancient hedges can have many more species than more recently planted ones, where the predominant species is often hawthorn, as it is cheap to buy and stock proof.

Last winter, no hedges, except those by the roadside, were cut on Wallmead Farm, because it was too wet to get any tractors into the fields without creating mud and ruts for months and the damage would be too much to remedy easily. 

Over the years, I have learnt that cutting should be as late as possible, and certainly not before Christmas, to let the birds and animals have time to eat their fill. Conservation subsidies help with the cost of hedge cutting if it is only done every second or third year, so that is what I have done too. The reason for this is that the flowering and therefore the fruit only happens on growth that is older than a year old. Yearly cutting results in no fruit at all.

When a tall and wide hedge is cut back, the result can look awful! With a flail (which all hedge cutters are) large stems are torn with a jagged edge and the hedge looks as if it has been mauled, a sight which I am sure is familiar to you all. The hedge does recover when spring comes and new shoots appear.

Before hedge cutters (going back 50 years or more), most hedges would have been laid on a rotation of about 15 years; hedges were radically thinned, and the remaining stems were cut at the base halfway through and bent to about 45 degrees to form an impenetrable barrier. 

This essentially is the advice to follow from The People’s Trust for Endangered Species, who have done research on this subject: to cut each two or three years gently, so it increases in height and width slowly, and then to lay it once every 15-20 years. There is a subsidy to help pay for this very slow and expensive job. 

​Peter Shallcross

As autumn approaches so trees and shrubs start to bear fruit and nuts. Chestnuts are marvellous in all kinds of recipes or simply roasted. These tasty nuts come from the sweet chestnut tree, a relative of the beech, and not to be confused with the horse chestnut, to which it is only distantly related. The latter is the one with large hand-shaped leaves, made up of up to seven leaflets, and which produces conkers from its showy-white candle-like flowers. The sweet chestnut, in contrast, has single spear-shaped leaves with serrated edges and less showy but often profuse flowers, which insects love. Both chestnut species have spiny cases in which the nuts develop. The spines of the sweet chestnut are more numerous and smaller than those of the horse chestnut.

Both species originate from hotter climates around the Mediterranean and have been introduced to this country. Sweet chestnuts were eaten by the Romans, but it is uncertain if the tree was cultivated here. The ones we can buy in the shops around Christmas are mostly imported. Nonetheless, the numerous small nuts our trees produce provide food for woodland creatures. Sweet chestnut trees only became common in this country in the Middle Ages, when they were exploited for its timber. It grows best in the south and east of England and is particularly well-suited for coppicing. The harvested stems are used for hop poles, furniture, charcoal, and fencing. The strong timber splits easily for use in wonderfully rustic and characterful cleft pale fences associated with Sussex and Kent. Sweet chestnut wood is essential to the construction of the distinctive Sussex trug, or gardening basket.

Sweet chestnuts can live for hundreds of years and grow to a great size. Ancient coppice stools can grow to look more like a small copse. As a maiden tree ages, the bark develops a network of diagonal fissures which spiral around the trunk. This can make them look as if a giant has grabbed the tree and given it a vicious twist. Veteran, stag-headed, specimens can end up contorted into sinister shapes, like the stunted one in the field south of Old Wardour Lake. If you want to see some splendid sweet chestnuts, take a walk up the drive to Stourhead House where there are several ancient monsters with girths of up to 8 metres.

​Andrew Graham

We are fortunate in southern Wiltshire to have more than our fair share of the county’s ancient woodlands. These are woods that have persisted since at least 1600, which is when maps started to become reasonably reliable so we can track a wood’s history. As they have a long-term continuity of woodland cover and management, such woods are often refuges for wildlife long since lost to the countryside. Some species are so specific to these woods, sometimes because they spread so slowly, that they are used as indicators to help in the identification of ancient sites. New woods planted on open land will never be able to develop the complex and rich biodiversity found in an ancient wood, so a mature woodland planted after the First World War may look splendid in the landscape, but from a wildlife point of view it may have little to offer.

Only 2.5% of the UK is ancient woodland, so it makes those remaining very precious. Although humans will have managed nearly all ancient woods at some time, and in some cases non-native species have been planted, the long-term tree cover allows for deep soils to develop, and complex wildlife communities to thrive. Dead wood, on which scarce fungi and invertebrates rely, can accumulate and archaeological remains such as earth banks and ditches may survive.

Just east of Salisbury lies a mosaic of ancient woods, the largest of which is Bentley Wood, which has an interesting history. The area was used to accommodate US troops in the run up to D-Day and then to store vehicles returning after the war. All this had an impact, but woodland continuity was maintained. After the Forestry Commission acquired it in the ‘50s, they filled any gaps created with new planting, until 1983, when the government wanted to sell off many of the Forestry Commission woods. At this point, a local resident stepped in, forming a trust to buy the wood so it could be enjoyed by the public. This was achieved in 1984 and for the past 40 years the woodlands have been carefully managed by The Friends of Bentley Wood for wildlife and public enjoyment.

The multiple tracks, rides and paths that criss-cross the wood are a pleasure to walk, and the site is particularly well known for the butterflies and birds found there.

​Andrew Graham

On Thursday 11th January at 7:30pm in the Victoria Hall on Tisbury High Street, we shall be hearing from Rob Farrington, who has been managing the Wild Woodbury Project from the outset.

​Rob will describe the work carried out to date, and discuss the prospects for the future and lessons to be drawn from this project for the countryside more widely.
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As always, our events are free if you’re a member of the Society or under 21, and you’ll be very welcome to come as a guest visitor for the payment of £2.

Many of us will soon be putting up our Christmas trees for the festive season. Decorated trees are a tradition imported from Germany by the royal family in the 19th Century. For me, the traditional species is Norway Spruce, but that has gradually been replaced by the Nordman Fir, which loses its needles less quickly. They are generally around 10 years old when cut and, with 6-8 million trees sold in Britain each year, most of which are grown here, their plantations cover a considerable land area.

Conifer plantations have had a bad press. There was a drive to create a national reserve of timber, after woodland cover reached an all-time low after the First World War. This resulted in large-scale afforestation of areas where soils were poor, often in ugly rectilinear blocks of single species. While young plantations had a short-lived boost in biodiversity, as the canopy closed, these woodlands often became lifeless. As conifers produce an economic yield up to 6 times faster than deciduous trees, and as the softwood they produce is in high demand for a huge number of uses, we do need these trees. However, management is very different today, large monocultural blocks are a thing of the past. More diverse mixes of species, planting which takes more account of drainage and landform, and the retention or creation of open habitat areas within the forest have become the norm. A number of conifer stands in an existing deciduous wood may increase diversity, while improving commercial viability. Many ancient woods have survived on this basis which might otherwise have been lost as woodland habitat.

More forests are now being managed on a continuous cover approach. This seeks to avoid extensive clear felling – taking out all the trees in an area at once – but to create more structurally diverse forests with a greater range of species under a continuous canopy. This avoids sudden changes in habitat conditions, to which wildlife finds it difficult to adapt, reduces erosion and could make the forest more resilient to risks from disease and changes in climate.

Obviously, this approach cannot be applied to the Christmas Tree plantations. However, as the trees are spaced to let the light get in, to create the conical trees we love, they can still provide a home for wildlife, especially if pesticides are avoided.

It is estimated that artificial trees generate 7 - 20x more carbon than a natural tree. So, if you do have one, it is essential to reuse it as many times as possible. But those of us sticking with natural trees can reduce the carbon footprint by sourcing it locally to keep down the tree miles and by disposing of it thoughtfully. A tree bought from a superstore may have been brought all the way from Scotland (and might have been felled weeks ago and so be ready to drop its needles as soon as you decorate it). The worst option for disposal is to send it to landfill; chipping, burning, or composting all result in lower carbon emissions. Wiltshire County Council will collect old trees from residents with green bins and compost them, or there are charities which collect them for recycling in return for a small donation.

​Andrew Graham

The day was sunny with that slight September chill in the air and we marvelled at the greenness of the trees in Savernake Forest for this time of year. After a wet May and then regular bouts of rain, the trees were showing fewer signs of stress and had kept their leaves longer. Keith Lea had prepared a fascinating day of study and exploration for us as we went off the main paths and visited different sections of the forest.

One of the first tips he shared was the way to differentiate pedunculate from sessile oaks by inspecting the way the leaves and acorns attached to the twigs. Our alliterative aide memoire of sessile-stalk will hopefully stick with us, where the sessile oak has long stalks to its leaves, whereas the pedunculate oak has the leaves forming from barely visible short stalks.

We had lively discussions about fungi, having spotted Shaggy parasol, Chicken in the woods, Beefsteak, Earthball and these tiny translucent white parasols perched up high on branches whose name we didn’t know. There were majestic ancient trees to marvel at and glades where trees formed circles round beaten down leaves and mast, or around grassy pastureland in the more open sections. Shifts in the scents of the forest and temperature surges were noticeable as we moved through the different sections.

​We had a truly immersive day in the life of the forest and Keith was an excellent leader, sharing his knowledge of the trees and wildlife. 

Much has been said about the need to plant more trees to help to lock up carbon to help address climate change. So, it is particularly upsetting to see recently planted trees that have died during our dry summer and others weakened by the drought shedding their leaves early. This stress is in addition to the natural diseases with which they must contend as a matter of course.

Unfortunately, there are also diseases which, in our global economy, were imported from abroad accidentally. One such is the fungus that causes Ash Dieback. This was first identified in the UK in 2012 although there is evidence that it has been present in Europe for 30 years. It originates in Asia where it does little damage to the local ash species, but our ash - Fraxinus excelsior - has no natural defences to it.

Ash is a common species and makes up around 12% of Britain’s broadleaved woodland so its loss will have a significant impact on the landscape. It is estimated that up to 80% of the trees will be killed, although as we are still the early stages of the epidemic, it is hard to judge. Whatever the losses, there will be an impact on those species of wildlife which rely upon ash.

The disease can affect trees of all ages although young ones, and those growing in woodlands with high proportions of ash, seem to succumb most quickly. Trees growing in open locations such as streets or in hedgerows seem less susceptible and there appears to be a level of resistance in some trees which, although infected, survive.

Local woodland managers have already been clearing ash trees and doubtless we will continue to see this in the years ahead. Those of us old enough to recall the dramatic change to the landscape caused by Dutch Elm Disease in the 1970’s will fear the long-term effect of Ash Dieback but will draw some comfort from the way that other species started to fill the gaps left when the elms were gone. But we must hope that further diseases do not erupt to thwart plans to increase our woodland cover as part of the essential work to lock up more carbon.

​by Andrew Graham

Dr. Peter Inness from the Meteorology Department of Reading University opened this fascinating talk, the last in our 2021/22 series of indoor meetings, with two images of the same patch of woodland near his Oxfordshire home taken two years apart to the day. In the first, the forest floor was carpeted with bluebells; in the second merely a green carpet with a few unopened bluebell buds visible. This was one of several illustrations he used to show how short term changes in weather can impact the natural world, as he sought to distinguish this variability from longer term trends.

In her recent PhD thesis a student at Reading had used data collected by volunteers across the British Isles (recorded on the Natures Calendar website managed by the Woodland Trust) to show that across the UK the mean first flower date for bluebells was 1st of May in 2013, but 8th April in 2017, fully three weeks earlier.

Dr Inness was able to explain this difference reflected short term climate impacts, rather than long term trends. Data for bluebell first-flowering dates and temperature records for January to April in successive years show that bluebell flowering dates respond to the weather and temperature conditions during March, February and January,  as the plant stems emerge and the flower buds form, rather than during the flowering period itself. And, though  invertebrates react rather more rapidly than plants, similar analyses for the first appearance of orange tip butterflies and for blue tits nesting reached similar conclusions.

In 2021, by contrast, hawthorn blossom appeared a whole month later than normal, reflecting an abnormally frosty April.

Looking at longer term trends and the impact of climate change, however, Dr Inness referred to  the paper published recently by the Royal Society. This used records on 406 plant species, some dating from as far back as the 18th century, to show a marked shift that took place in the 1980s. Plants are now emerging on average a whole month earlier each year than seventy years ago.

He showed projections prepared by the Meteorological office to indicate that by 2050, in every other year we will experience summer temperatures similar to those we experienced in the very hot year of 2018. And, unless significant reductions in greenhouse gas emissions are achieved globally, these temperatures will be the annual norm by the end of the century. And he also showed projected rainfall maps clearly showing that our winters will be wetter and summers dryer, and warned that individual rainfall events will be 29% stronger. A new UK record for of 316mm rain in a 24 hour period, set as recently as 2009, was surpassed again only six years later in 2015 with a new record of 341mm.  All of which suggests that nationally there are considerable tasks and costs ahead to prepare reservoirs and infrastructure to be able to cope.

From a wildlife perspective these climate trends are complex and deeply concerning. Dr Inness gave as examples the likely impact on the relatively shallow root systems of beech trees, less well adapted to cope with summer drought conditions than deeper rooted oaks. And the impact on populations of birds such as swallows whose northerly migrations are triggered by seasonal changes in daylight hours. They may arrive at European destinations too late to feed their young on invertebrates maturing earlier as a result of warmer Spring conditions.
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Troubling as these issues are, the talk was hugely valuable and timely, providing us all with deeper insight into the impact weather and climate have on the natural world around us. 

by Richard Budden