Posts tagged ‘nature’
My article celebrating the 350th anniversary of John Evelyn’s 1664 Sylva has been published in the international weekly journal of science Nature.
Hemery, G (2014) In retrospect: Sylva. Nature, 507, 166–167, (13 March 2014), doi:10.1038/507166a
July 4, 2012
Our Forests member Jonathon Porritt, explains why he thinks it is that we love our forests and trees so much we are willing to fight to protect them. Watch the film.
We’ve had some really stormy summer weather in the UK over the last week or so. Unlike those intrepid fauna nature photographers, us plant photographers are normally lulled into a false sense of smugness that our subjects stay still long enough to allow us to frame every shot taking all the time we need. Wind however is a game changer.
I have written before about photographing trees in the wind. In that post I explained, perhaps counter-intuitively, how using a long exposure on windy days can create interesting results – read the post here. This weekend I came across some wonderful old farm buildings and the contrast of their rusty corrugated iron with the stormy sky was compelling, and both provided great features to some images I wanted to capture of elder Sambucus nigra.
I came to this first elder because it was sheltered from the wind by the building. I liked the perspective offered by its dark empty windows and how they led to the elder as the focal point in the image. The roll of fence netting in the foreground offered some interest without detracting from the main subject on the middle distance. The ash tree far left provided a helpful sense of perspective. I wasn’t sure about the powerlines overhead. I was in two minds whether they added some sense of the industrial or whether they detracted – what do you think? I suppose I could remove them in Photoshop but that’s not my style.
I resorted to a long exposure times for this second photograph (below), wanting to contrast the movement in the plants with the rigid structure of the collapsed old farm buildings. I aimed to accentuate how much the vegetation was moving in the wind by increasing the exposure time (using a slow shutter speed). I used a neutral density filter (x8) to reduce the light entering the lens; meaning that I could use a longer exposure time. I also added a polariser filter to further increase exposure, with the added benefit that this enhanced the stormy clouds. Lastly I set my film speed to the lowest on my camera (ISO160) and my aperture to the smallest (f22); both with a view to increasing exposure time. With all these steps the correct exposure in the bright summer light was 0.6 seconds; just enough to really capture the swaying trees in the background and the moving grass in the foreground. Naturally I used a tripod (Benbo Trekker) and cable release. I fired off lots of shots, waiting to coincide them with the strongest gusts. For just one frame I was in luck when a blackbird perched atop the elder that was my main interest, providing a great focal point in the image.
I’ve included both these pictures at twice the size I normally upload as their detail is better to explore at this size. Both were captured as RAW format and processed using Adobe Lightroom.
Black poplar Populus nigra (subspecies betulifolia) is a tree native to Britain and well-adapted to our floodplains. The species is widespread across the country but never common.
Black poplars often lean, and when in leaf their characteristic diamond-shaped leaves (cuneate leaf-bases) also help in identification. Female trees are very rare and so many trees in our landscape are clonal in origin. Due to conservation efforts to increase the number of trees, when at one time there were thought to be only 7000 left in the country, the species has been planted widely across the country.
I found a group of eight mature black poplars near Wallingford in Oxfordshire. The dramatic clouds added a dynamic touch to the composition of the photo and the low angle of the sun added tone and texture. To avoid lens flare I placed the camera, mounted on a tripod, precisely so that the sun was hidden partially behind the stem of the nearest tree.
Photograph: Lumix GF2, 7mm (14mm in 35mm equivalent), f11, 1/200sec, ISO100. Tripod.
I captured the shadow of a very large and healthy Cornish elm Ulmus minor subsp. angustifolia growing in East Sussex. It is one of the last large elm trees remaining alive in England, following the spread of Dutch Elm Disease, which has all but wiped out the majestic elm. The dark chasm depicts figuratively the loss of the elm in the English rural landscape.
I used burn and dodge tools in Adobe Lightroom to create the effect of a chasm in the ground. I left a subtle hint of colour amongst the darkness to help suggest depth (visible at full size). Some small adjustments of greens and yellows helped enhance the already strong tree shadow in the grass. Taken with a Lumix GF2 with 7mm lens (14mm at 35mm equivalent), f11, ISO100.
March 22, 2012
The fungus that wiped out 3.5 billion chestnut trees in the USA has been found for the first time in Britain. Chestnut blight, caused by the fungus Cryphonectria parasitica (C. parasitica), has been confirmed by Forest Research scientists on trees in two small orchards of European sweet chestnut (Castanea sativa). The trees were imported by an English tree nursery from the same grower in France. The sites in Warwickshire and East Sussex are the first findings in Britain. Until now, the English Channel had prevented its spread from mainland Europe.
The fungus infection is usually fatal to European sweet chestnut and its North American relative, Castanea dentata, although it appears to be less virulent in Europe than it is in America. It is believed to have first originated in Eastern Asia before being introduced to North America in the late 19th Century, where it has since devastated billions of trees in the East of the country (see The American Chestnut Foundation). It was first identified in Europe in 1938, in Italy, and has since spread to most parts of southern Europe where sweet chestnut is grown, and to parts of northern Europe.
Identifying chestnut blight
The most obvious symptoms of chestnut blight are wilting and die-back of tree shoots. Young trees with this infection normally die back to the root collar, and might re-sprout before becoming re-infected. Other symptoms, such as stem cankers and the presence of fruiting bodies can also occur.
The trees where the fungus were discovered had been imported into the UK for nut production. As I have written before (e.g. Climate Change and Global Trade), the import/export of trees is potentially the most significant factor in the spread of new tree pests and diseases. Case proven I think. Let’s hope that FERA (Food & Environment Research Agency of the UK Government) is given adequate resources to tackle this very serious fungus. Afterall, sweet chestnut is a beautiful tree species in our forests and when coppiced, as it is in commonly in Kent (see Sweet Chestnut Coppice), it is one of the few forest systems that pays well and regularly.