We have been addressing this problem for almost twenty years and we have a simple new insight in terms of mechanization.
We have already come to understand that a working woodlot demands proactive grooming and rotational grazing for optimal productivity. This can also be achieved once your forest becomes a climax forest, but that is centuries away and then, not so wonderful in terms of economic productivity.
Proactive grooming requires knocking down branches to above your head and maintaining an open spacing to allow at least 60 percent sunlight gettting to the forest floor allowing surface vegetation as animal fodder for a likely flock of sheep and perhaps cattle.
This is pretty good and somewhat describes our orchard practise. The difficulty is the next fifty feet or so. what I just figured out is that we can dfrive up to a given stem and use a clamping device to grasp the trunk an use that to stabalize the 0machine itself. We can then use a bucket on an hydraulic arm to move up the tree without fear of toppling over. This is huge.
If we are working with pine trees in the boreal forest, we can immediately drop the lowest ring of branches and open a clear path on one side to the tree top itself. At tree top we can easily harvest mature pine cones into a burlap sack to finish the task. If this is done every year we collect an annual pine cone harvest and also produce a clear stem that only has knots in the six inch core. The final stem will be robust and as tall as any mature pine tree orr any other conifer as well that we chose to work this way.
Branches on the ground can be chipped the next spring if we care though grazers will break them up as well.
If we are working with fruit and nut trees, we are no longer restricting ourselves to dwarf root stalks and we will care about the end quality of the stem. After all a long apple wood saw log will be valuable when it is harvested at say fifty years.
with such trees, this tech allows harvesting with a bucket as well. if it is necessary but also allows us to send a clamping claw up to a robust higher limb and to shake all the fruit off just as we now do with the whole tree.
My interest in the pine forest is because we can select for pine nuts and excellent stems and even ship wood chips for pulp. This allows us to fully operate our entire boreal forest using such forest husbandry. This is highly important to Canada and Russia in particular. Yet it is a natural default throughout the USA. After all they are fast growing and get there first. With a bucket on a crane a harvester can get up to the crown and easily pluck all the cones that are there in a few minutes without a lot of fuss.
A sack of cones are then set in a shed to dry for a long time which finally pops them open after which a shaker table separates out the nuts. The cones can then be sent through a chipper for either biochar production or even the compost heap. They will not go to waste then.
By and large, most tree species have a good fifty year growth cycle to harvest. They can obviously go a lot longer but by then you have decent stem for a saw log. without any grooming, you will want to take them down then anyway. So a planned grooming system can produce annually wood chips, and an annual harvest now easily accessed with simple powered equipment. Better yet the annual labor input is actually light. Once groomed, we can harvest a pine crown in perhaps twenty minutes and then on to the next tree.
We will be also be able to do this with drones and we can save the bucket crane to dropping a ring of branches. My point is that a groomed forest is and will be always economically valuable and we will never give up wood