MIND YOUR HEAD!
A tree fell on my head yesterday. Just a little tree, of course; more like a branch. But I was doing the usual forester’s thing of never looking up and whizzing along the rows without a thought to what was above my head. It is the first rule in forestry; always look up. The butt of a tree can be as smooth as silk, the stem well formed and straight. But if the top is forked, the leader suppressed, other trees too close or if, towering above the precocious sapling is a forest of mature trees blocking out the light and preventing proper formation, then all will be for nothing. Always look up; that is where the tree is going. (And of course, never plant under overhead lines. It is amazing how many people do. I do.)
WEAR THE RIGHT KIT
I am thinning a 17-year old plantation of Larch and Beech, alternate lines. The Larch are forty feet tall, worthy of respect and given it. The Beech are miserable stunted bushes, half the size at most, easy to treat casually; but they land with a thunk on my pate even so. So that is the second rule: wear the right kit. Helmet, earplugs, goggles, gloves, trousers and boots may seem over the top for a small wood of adolescent trees, but accidents happen because they are unexpected. My neighbour swallowed his tongue while felling an Apple tree, and I lost sight in one eye for several days when whipped by a raspberry cane. Even the meanest tree can hurt; respect it. And think.
TEDIUM CAN BE USEFUL IF YOU USE THE TIME TO THINK
So much of forestry is dangerous, sweaty and boring. Going up and down those lines of trees, weeding, pruning or thinning, is drudgery, physically demanding and mentally dead. I should be learning sonnets or practicing my Greek irregular verbs; instead I nurse historic grievances. At least farmers, once a month, have to shave, and brush their shoes, to go to market. For a forester, years can pass without human contact. I would go mad from loneliness and boredom if I did not reflect on why I do things, and how to get it right.
Over the last twenty years, we have planted or replanted about 100 acres with an even mixture of species: sitka, Larch, Norway, Douglas, Scots, Oak and Beech. I have not planted Ash, Sycamore, Spanish Chestnut and Birch, but they have grown themselves and been managed. I have put time into early and repeated weeding and shaping, particularly the broadleaves. But the cycle has moved on, and I am now doing more thinning, and (in between the grudges and groans) thinking more about species mix, and management.
IDEAS ON SPECIES MIXES
First, species mix. Obviously, Larch and Beech do not go, the Beech having been suppressed from the start. But I believe in putting Beech with most things, if only because it helps suppress the weeds and give a balance of light and shade. I would never put Beech with Sitka, where it would add nothing. Nor to a mix of small native trees (Crab Apple, Birch, Mountain Ash etc) which would be my choice, if I were planting only for the grant or for amenity. But with Oak or Douglas, or anything in between, bung in the Beech.
It is a matter of taste whether you plant the different species in rows, or blocks, or discrete compartments. I prefer adjacent rows of alternate species (perhaps a double row if the tree is a relatively slow grower). It spreads the propagation risk across the field, and provides a more intimate mix in the end. I am not normally worried about differential growth rates of two different adjacent species. If you thin to favour the best stem, you are likely to cut enough spaces to give most secondary species a chance.
And you must of course thin to leave the best stems. I get apoplectic when I read forest management plans stating “thin to favour x”, as if one species is so morally superior to deserve preference even if it is manifestly unsuited to a site. Equally, if your sitka plantation has failed and is sprouting birch, do not grub them up at vast expense. Simply grow birch. But only manage them; make sure that they are the best Birch you could grow. Otherwise you are wasting the land. Leave what is growing well, cut out the rubbish, and do not worry about gaps. There is no point in leaving a poor specimen just to make up numbers.
Secondly, management. And again, personal preference must decide. In an ideal world, thin little and often, allowing the selected final stems (it is all a bit Brave New World) incremental growth to fill their given space, by judicious removal of adjacent stems and branches, but avoiding excessive light which encourages lateral growth, epicormis and weeds. In practice, we have all got other things to do. I need to gear myself up to do something, happily finding dozens of other jobs around the place, just to put off That Which Must Be Done. And then the right saw needs mending, the chain is blunt, and the oil and mix have run out. So that, once I am into the job, I do not want to stop until it is finished and mentally ticked off for the next five or twenty years. When I thin, I thin hard. But you will have your own ideas.
DECISIONS ABOUT THINNING
Next, do you thin to individual stems, or rack, removing all trees in a row? It depends on circumstances. If you grow conifers you may be lucky and get a machine to rack (take out entirely) every third, fifth or seventh row, allowing you to get a tractor into the wood and pull the intervening trees to the rack by hand. But you will have to pay. Around here, I could neither give away my first thinnings nor even pay somebody to do it. I have to do it myself. And I have an instinctive dislike of wasting one third, fifth or seventh of my best trees. So I do everything selectively, and shape all the good trees and cut out the rest, wherever they are. I do not mind the resultant clumps and gaps.
Finally, how to use the thinned trees ? Cutting them is easy: whizz, whizz (thunk, ouch) whizz. But these are likely to be the worst stems, and many will be useless for firewood, timber or stakes. Fifty years ago, first thinnings had some value; now they are a cost. How do you get rid of them? On those many private estates in Britain, where forestry is still practiced as an art, all thinnings are taken from the wood for disposal. Alas; not here. Full marks, if you can get them out. But if your living is from forestry, you may want to consider other ways. I have two suggestions; but any forestry visit will offer others.
If the thinnings are reasonably light (Larch, Oak, Beech etc), I cut down, chop up small and stack tidily in the wood. This provides good habitat, particularly if the tree species prevents much undergrowth. The stacks will rot over time, but they will be a nuisance until then. So the job must be done right first time. Another way is to try to kill the tree standing, perhaps by cutting through much of the base, but not all, or spraying weedkiller into a wound. This leaves the tree standing, preserving the shade of the adjacent trees. But it is difficult to get right (too much, and the tree dies and fall over; not enough, and it keeps on growing).
However you do it, it is all work, and no short cuts. The first step (aged 15-20) is to cut off all the lower branches with a small foot-long chain saw, and single any forked stems which are common among hardwoods (particularly Ash). You must do this first, and do every tree. First, it clears all the brambles; second, it allows you to see the wood properly. I brash (cut off the lower branches) of all trees, even if they are due to be thinned. It makes felling easier and whether you remove the poles or chop them up to rot on the ground, the branches have to come off some time anyway. So do it right first time.
YOU HAVE TO THINK ABOUT THE NEXT TIME
And then, whether or not you use a quad or a tractor, and clear the thinnings or leave them to rot, you still have to chop up the lop and top. You must be able to get back into that wood when the time comes, five years later or twenty. Because the next thin, the second thin, is the crucial one: then, you might make some money and, most importantly, you will determine the future of the wood.
Ireland’s tree magazine – Spring issue 2006
Jack Tenison is very much a “hands on” forester and woodland owner in South Wales and Lough Bawn, Co. Monahan, Ireland. He writes regular articles for Crann Magazine and has helped Irish timber growers by hosting visits and demonstrating his successes and failures on his wooded estate.
Jack was an early member of Woodland Heritage and is a great supporter of the European Squirrel Initiative.
We featured his work in Woodland Heritage Journal No. 8 – 2003, page 17.