I think it would be very unusual for two trunks to fuse (inosculate) other than at one small area. The bark must be rubbed away for the cambium layers to meet and grow together. This is unlikely to occur naturally at more than a point and very unlikely to occur at the base of the trees. When it occurs, it's usually where two branches are in constant contact and blown by wind to remove the bark. In situations where two tree trunks are growing side by side, normally, they don't every truly fuse. Even if they look as if they do, when cut, the trunks are not fused. Very often, when two trunks meet in this way, rot will occur and sometimes will be the cause of premature tree death.

Hi Brandon,

That is very disappointing: that the rot will occur and sometimes will be the cause of premature tree death. In nature, I've seen enormous threes that seem to survive this natural arrangement, or maybe I'm not interpreting the observation correctly: there are 4+ large trunks that are growing so closely that, for the first few feet, the run in parallel contact with one another; maybe they are not 4 separate trees (of the same species and size) but 4 separate suckers coming from the same root system.

Maybe a way out of this issue is to get this to happen early on: to arrange the 4 saplings (that are of 1" diameters or so) only 2" apart from each other; to me, it would seem that this would have to cause a single solid tree trunk of the 4. I hope I can figure this out soon, because the saplings are on their way in the mail and are bare root.

Thanks,
Steve