Has anyone tried bark inversion?
I have successfully used it on citruses. It can control the growth of citruses without pruning and it induces early blooming for citruses grown from seeds. The major advantage is that the tree size doesn’t grow vigorously and so you don’t need to prune for about 4 years and then you do light trimming and another bark inversion again. You do this when you want to maintain the size of the tree, citruses specially because if you prune citruses, especially snipping off the terminals, you would have severe reduction in fruit production.
Bark inversion has been practiced by utility folks in Canada to maintain the roadside trees so they only need to prune the trees once a while instead of every year and saves a lot on labor.
Basically, you remove a ring of bark near the base of the tree on the main trunk, pull it out the ring of bark, turn it upside down and put it back and seal with parafilm. It reverses the polarity of the cambium in the ring of bark, limiting but not stopping the supply of nutrients into the roots. Without big roots, the tree remain small and so it concentrates the photosynthates into fruit production, improving the quality of the fruits. Similar in effect to mild girdling done on grapes or on selected branches of citruses.
Here’s a tutorial that I did to illustrate what Bark Inversion is all about. Make sure to read the descriptions on each picture as it has very good explanations and minor discussions about each step.