A plant is considered to be ‘inosculate’ if it is self-grafting; if the branch of one individual will, as the result of gentle abrasion, form a living bond with the branch of another individual, or with another branch of the same plant. When this grafting is aided or initiated by humans, the process is called 'pleaching.’
In mediaeval Europe, in areas where annual flooding endangered human settlements, the pleaching of inosculate trees was employed as a solution to what otherwise might have been an insoluble problem. The trees were planted on a grid, like a small orchard. As they grew, branches were pruned and trained along this grid, so that eventually the branch of one tree met that of its neighbour. At that point, an incision was made in the bark of both branches and they were tied together, like blood brothers or sisters. The analogy is deserved, in that not only did these branches grow together to form one member, but their support activities (condition of water/minerals and sap) merged, thereby joining the life processes of the neighbouring trees.