Update from Orginal Author : Jacob Northman Guild
Marcus Vitruvius Pollio commonly known as Vitruvius, was a Roman author, architect, civil engineer, and military engineer during the 1st century BC. In one of his books about Roman Architecture he wrote following about the lost technique of forgotten forestry injuring growing trees on purpose: "In felling a tree we should cut into the trunk of it to the very heart, and then leave it standing so that the sap may drain out drop by drop throughout the whole of it. In this way the useless liquid which is within will run out through the sapwood instead of having to die in a mass of decay, thus spoiling the quality of the timber. Then and not till then, the tree being drained dry and the sap no longer dripping, let it be felled and it will be in the highest state of usefulness.
That this is so may be seen in the case of fruit trees. When these are tapped at the base and pruned, each at the proper time, they pour out from the heart through the tapholes all the superfluous and corrupting fluid which they contain, and thus the draining process makes them durable. But when the juices of trees have no means of escape, they clot and rot in them, making the trees hollow and good for nothing. Therefore, if the draining process does not exhaust them while they are still alive, there is no doubt that, if the same principle is followed in felling them for timber, they will last a long time and be very useful in buildings."" Marcus Vitruvius Pollio, 20 AD, Rome
Those experimental trees injured in those pics are going to be taken down this month after 2 years of waiting. There are two common wood injuring on purpose techniques known in Scandinavia and Baltics. 1. Ring cutting, barking. You measeure the depth of sapwood of the pine tree and axe a groove around the tree untill the heartwood. Make several spot injuries with an axe as high as you can get. Wait 1-2 years and cut down the tree during winter and empty moon. You will get a tree that has less sugars, water and nutrients in it what attracts fungi and blue stain. Pine after 2 years will still have needles in the branches but it is slowly dying as cutting the ring stops the nutrient transportation up the tree. All the suggars will filter out that ring. This way in Norway was prepared wood for stave churches. 2. Strip barking. You make lognitudal stripes on 4 sides of the pine at about 9 meters height. You do it in spring before juices start to flow. Next spring you remove 3 more stripes of bark/cambium - leaving it only on one thin stripe. After another year in spring you remove the last stripe and skin the tree completelty. All the rest of the injured places are infilled with pine resin and has closed pore structure. In the 3rd years winter by thr empty moon you fell the tree. You get 9 meters of round log that does not attract water and is copletely preserved by the pine resin. Such logs were used for round log structures - log cabins and round timber frame. I will fell the trees and post my experiment results in Northmen facebook and IG pages.