Earlier this week I spent a few hours processing firewood with hand tools. Unlike when using a chainsaw, the hand tools allow time for thinking, and this post is partly about the firewood, and partly about the thoughts that went with the activity.
The picture above shows the tree that I worked on. It is a copparded ash (COPPice/pollARD). The dark healed cut to the stump shows the last cut that I made, some time over the last five years or more. Some of the regrowth has reached 5 inches in diameter, which is as thick as I want it for firewood. Any bigger, and I would have to start splitting it, adding another chore, which isn’t needed. The saw shown is a japanese pruning saw. It will cut limbs of 6 inches with ease, and is perfect for working pole wood.
One of the things that occurred to me whilst I was removing the limbs, was how would I have cut the original trunk without a chainsaw? It reminded me of accounts quoted by Oliver Rackham, in ‘History of the Countryside’, where medieval landlords were complaining of their tenants ‘ringing’ timber trees, to turn them into pollards. At the time timber trees were the property of the landlord, as were the trunks of pollarded trees, but the growth of the pollards belonged to the tenants. Ringing, turned timber trees into pollards, benefitting the tenant, at the expense of the landlord. I’m guessing that ringing meant ring barking, where a section of bark was removed from all around the trunk. This has the effect of killing the growth above the ring, and the tree puts up new growth from immediately below the ring. I’m also guessing that with the top growth dead, eventually it would fall in strong winds, completing the job with nothing more advanced than a blade.
What comes across strongly in the book is the large amount of wood in the hedgerows, and in the form of timber and pollard trees, in what is described as wood pasture. An early example of agroforestry, or silvopasture.
After about an hour, the polewood was cut into sections suitable for our woodburning stove, using a bowsaw. Again, a nice steady job, not too taxing, and allowing time for thought.
The next thing that crossed my mind, and was pondered upon, was the need to actually ‘do’, rather than just read about things. I’m sometimes asked how much wood it takes to heat a house, and how much land that takes. The answer is ‘it all depends’. There are too many variables to be able to calculate that with any accuracy We use less than a wheelbarrow load of wood per day to run our woodburner, and it takes me less than an hour to process that much firewood, which is quite a good return. The picture below shows the end result of about 3+ hours of steady work.
That equates to about four wheelbarrow loads, but as some the wood is quite thin, it will burn a bit faster, so perhaps three days of heating. The majority of the time was spent sitting down, cutting the thin stuff for bags of kindling. Sometimes I don’t bother with the small stuff, and have been using it as a soil conditioner around my newly planted trees, but as this is ash, which burns so well, it was worth the extra time spent.
The actual question is still quite hard to answer. If you look back at the first picture, the thin trees behind the stumps are beech planted about ten years ago. Their growth has been held back by the ash, and by other trees in the hedge. The picture below shows an oak copparded ten years ago. Just to the left, below the cherry laurel, the little white blob is a chicken, for a sense of scale.
The picture below shows the bottom section of the same tree. The thickest limbs are about 8 inches thick. To return to the question of how many trees you might need. This tree stands out in a lawn, and therefore gets full sun. The total spread is about 6 meters (20 feet). When I process this tree, I can work out how much wood it has produced in ten years, and calculate how many trees per year I would need, and then multiply that by ten years to give a total. This would enable me to work out how much land it would take. Again it isn’t that simple. The ash processed gave less wood, but from a hedgerow of closely spaced trees. Even at a 2 meter spacing that would give 9 times as many individual trees. So which option would be best. For me, with no livestock bigger than poultry, it’s not so important, and the close spacing would probably suit the poultry better, but a grazing system for cattle would do better with fewer, but larger trees. The site is also important. My trees grow on clay, and will grow at a different rate from those grown on other soil types, and from alternative tree species.
That led me to consider planting densities in more depth. Even were you to get, or give advice about tree spacings, unless you see it for yourself, it’s sometimes easy to forget time as a factor. For example, you might think/read/be told that you should plant oak at 6 meter spacings, and cut on a six to ten year rotation. That will give you a total number of trees to plant. However, if you look at the picture below, it shows some ten year old ash saplings, and a willow. If I had planted them at wider spacing, and thought that my first cut, at ten years, would produce a full load of poles, I would have been very disappointed. If you look at the growth of each sapling, with that of the earlier oak, there is no comparison. Even when added together, the total growth is still considerably less than that of the oak. Some of those trees will eventually produce a lot of wood, but not yet. By planting at a much higher density, I can increase the yield of the space, and then slowly thin to the final spacing. There are other benefits, but they can wait for another post.
This may read like common sense, but I think that you would be surprised how frequently people get it wrong, either on their own, or on the advice of ‘experts’.
The key here is that there is no substitute for experience, there are some things that you can learn from a book, and I read more than most, but sometimes you actually have to do something to truly understand it.
Wishing you well