More interviews this week, and the new apprentices should be starting their block weeks in November.……. not long now!
Talking to more potential recruits this week it reinforced the fact that I rarely come across people who want to be Arborists from the word go. We have this constant parade of people who have drifted in from elsewhere and it seems to be something that you generally come across by accident. I have visited many schools and colleges over the years to talk about my vocational area, but I have never met anyone who, from the age of five, had wanted to be an Arborist, and to be honest, I am usually happy if they even know what one is!
I hadn’t even heard of tree surgery, until that fateful day back in 1984 when I met the guys from Cardiff Treescapes……
When interviewing people for roles at The Academy, the same things keep coming out, people get into Arb because they like being outdoors, like hands on practical work, like a challenge, like every day being different, and if I’m lucky, like trees! I can understand this, I have been in Arb over 30 years, and although I can’t honestly say that I have skipped and sung my way into work every day, there is no denying that what these interviewees say is true. Every day is different, rarely boring, hands on, stretches you physically and mentally sometimes, and most of the time I can’t think of a better occupation. It’s also a job that gets under your skin, and becomes a passion. I find my knowledge of trees is being constantly expanded, I want to learn more and I never stop being amazed by what my studies turn up. To find yourself in a job that you love, that interests, inspires and motivates you every day can only be said to make you very lucky…. and now I get to tell other people about it as well, whether they want me to or not- lucky people!
So a big welcome to the class of 2017, I hope that they find working with trees as fascinating and inspiring as I have, and if we at The Academy can help them with that, then we are doing our jobs properly.
FOCUS on………. Clones, Coppice, Pollards and Coppards
The picture above shows a section of small leaved lime woodland on the banks of the River Dart. If you look at the picture closely, you will see that the trees are all growing in multi- stemmed clumps. This is because the trees are growing from a common stump, and it is possible that these stumps were initially cut by people hundreds of years ago and have kept growing back. These cut stumps are commonly called ‘stools’. When trees are cut down to ground level, it is called coppicing, and they are usually called ‘coppice stools’. It is an ancient and traditional method of harvesting wood from trees, the system creates many long straight pieces of wood, good for lots of things, such as charcoal, timber, firewood and produces loads of leaves for animals to browse as fodder. The downside is that all the new growth is at ground level, and so can be eaten by deer and rabbits unless you find some way to keep them out. The upside is, that if you can keep the animals off, this sort of management can extend a trees life for many hundreds of years, and give you lots of browse, charcoal and timber over centuries.
Here’s another lime tree, this time it’s a large leaved lime. The branches are all growing from a common stem rather than stool here, so all the new growth starts over head height. This is called pollarding. It’s a bit more difficult than coppicing, in that you have to climb into the crown or work from a ladder to harvest the stems. The stems, also eventually decay and decline, as you can see with this ancient specimen, and you have to keep cutting them to prevent them falling apart.The upside is that all the new growth is kept above the height of browsing animals, so it doesn’t get eaten. This tree is in an old deer park, hence why they tended to coppice trees here, and keep the delicious lime leaves above deer height. In fact young lime leaves are quite tasty, and can be eaten in salads. I find, though that you need to get them really young, and when they are not too hairy or bitter, or they aren’t so great!
You can’t coppice or pollard easily with all species, but some like lime, hazel and sweet chestnut are very easily cut and will vigourously regrow. Others such as beech, hornbeam and oak, take a bit more care, but can be encouraged to regrow if cut in a particular way.
Once people stop managing pollards, coppards and coppices, they become ‘lapsed’ and you will often hear people talk about ‘lapsed coppice’ or ‘lapsed pollards’, and in fact the first picture is a good example of lapsed coppice.
It also seems to be a scratching post up to cow bottom height!
This tree is probably several hundred years old, and is in excellent health- great news, but being an elm, this isn’t often the case and they rarely get to be majestic old trees anymore.
Most people will have heard of Dutch elm disease. It has eradicated most of the large elms from our towns and countryside, the most you now regularly see are the bleached dying elms around 10-12 feet high in the hedgerows. Elms grow to a height and diameter where a particular beetle can find them, and then once it burrows into the tree, it carries a fungus with it, which results in the death of the upper part of the tree. The roots, however survive, and put new shoots up which grow for a decade or so until they are the right height and size for the beetle- and so the cycle goes on. Wych elm is also susceptible to the disease, but does seem to have some fairly healthy, older specimens such as this. Whether it is luck or genetics it is hard to tell, but there is a big difference between small leaved lime, common elm and other trees such as the wych elm here. Trees such as small leaved lime and our common hedgerow elms, don’t set good viable seed in this country. They are at the northern end of their range, and the seed just does not germinate. That means that if they are to colonize an area, they have to use a different strategy…….
Trees like limes and elms are very good at propagating themselves from their surviving root systems and from these ‘suckers’. So the tree will keep spreading from the initial stool outwards, slowly taking over an area. It’s great at getting you out there, if you can’t set seed, but unfortunately, as we have seen, all the suckers are genetically identical, so if a disease such as Dutch elm disease gets into the population, they are unlikely to show much resistance and will see a huge drop in population numbers. This happens time and time again with isolated populations of plants and animals, and even where there is genetic diversity, there can be a lack of resistance simply because that plant or animal has never been exposed to the pest or disease before. Setting seed means you have more genetic diversity, because seed usually requires input from two different parent trees, hence why there is a chance of some difference in disease resistance. Cloning yourself is a risky strategy, but in an isolated population, it can work. Unfortunately, we aren’t isolated enough, and pests and diseases are able to blow on the wind across the sea from Europe, or more commonly they are imported by humans, often accidentally on timber, packaging or as plantings. The last influx of Dutch elm disease was brought in on infected timber from the USA, and produced a particularly vigorous hybrid fungus that the trees had virtually no defences against.
We need to be more careful with our biosecurity, we don’t take enough care when we import plants, or animals from abroad. We are seeing large spikes in the numbers of pests and diseases threatening our trees, due in large part to our own activities. We’ve had Dutch elm disease, and now we have already here and waiting in the wings, ash dieback, sweet chestnut blight, plane wilt, emerald ash borer, chestnut bleeding canker, acute oak decline, sudden oak death and many, many, many others.
Our treescape will be unrecognisable in 50 years if we do nothing.
Anyway, on a happier note, here is a poem that I used to pin to my desk to remind me what other people think about trees, and why we need to preserve and nurture them for future generations.
by Harry Behn
Trees are the kindest things I know,
They do no harm, they simply grow
And spread a shade for sleepy cows,
And gather birds among their bows.
They give us fruit in leaves above,
And wood to make our houses of,
And leaves to burn on Halloween
And in the Spring new buds of green.
They are first when day's begun
To tough the beams of morning sun,
They are the last to hold the light
When evening changes into night.
And when a moon floats on the sky
They hum a drowsy lullaby
Of sleepy children long ago...
Trees are the kindest things I know.