I spotted this illustration of forest management on the blog Small Dead Animals. I’m 76, and doubt that I have enough working life ahead of me to bring 120 long neglected acres of forest into the condition it needs – but I have started, and maintaining the old roads and skid trails does serve a purpose in being able to respond to fire.
My forest is overmature – the reason for getting a sawmill was that not all of the large trees were merchandisable timber in long lengths, but it is much easier to convert a shortlog into lumber. Years ago, I remember the advice for thinning was take the DBH (diameter breast high) in inches, change it to feet, add 7, and that would be the distance between trees. Basically, if my woods were properly thinned, it would be easy to drive a tractor through the trees. I’ll keep pecking away at it.
The other thing is grazing – the comment I learned early was that a properly thinned forest provides 80% of the grazing that would occur if it was open ground. Here that probably translates to the difference between a tenth of an AUM (animal unit month) of grazing un-thinned and 3 AUMs if the trees were spaced 17 or 18 feet apart (it isn’t totally unlike demography – though this is a bit more like Thomas Malthus’ views). So if I were to look at 100 acres of crowded timber, I might be able to graze 2 cows for 5 months – where the same timber, properly thinned, would produce more harvestable logs and enough grazing for 6 cows. The logic is irrefutable. The labor is a bit much for a man of 76 – but maybe my grandsons will see completion.
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