The reason for the early demise of a tree, not only a fruit tree, is usually either its mechanical instability, or gradual withering due to the low intensity of photosynthesis of small leaves on old wood, when the tree actually slowly suffocates. Mostly it is a combination of both of these reasons, or less efficient leaves play a more fundamental role in the aging process, as they will cause premature death of the tree even if no decay of the tree occurs. In any case, both causes can be effectively countered by a correctly performed cutting intervention.

So how?

We always adjust the growth conditions of the entire tree, not just some parts. In natural development, the tree gradually gives more energy to the higher parts of the crown. We try to fight against this natural process by cutting, and thus we suppress the upper branches competing with the lower ones. Of course, we respect the growth peculiarities of the tree. We always carefully monitor which branches the tree no longer gives much life force to, and we remove them as a matter of priority. It is certainly not a good idea to forcefully cross paths where the energy is in full flow.

The rule applies that the lower branch, if it is at least a little perspective, has priority over the higher competition. A wrongly cut branch at the bottom of the tree will never grow back. One of the problems with unmaintained trees is that the shaded lower branches wither away and so-called dead spots are created… So we prune more at the top than at the bottom, where we tend to just prune. Basically, we cut down the branches on a younger, advantageously placed offshoot.

What is quite important is the time of the rejuvenation cut. If we have the chance to choose, we choose February or the beginning of March, when there is no longer any danger of frost. With core crops, there is no need to worry about cutting even in December, when it is not freezing. Especially in the case of trees that are no longer growing at all, it is important that the rejuvenation procedure is carried out before the tree starts to wake up and the sap starts to circulate in it. If we had cut until sometime in April, we would have removed a large part of the assimilate reserves with the branches, and the subsequent growth would not have been as vital, just as so many dormant buds would not have awakened.

In the case of stone fruits, we only cut before or during the flowering period, with cherries it is also advantageous to cut during the harvest. It is not out of the question to cut the branches even before the tree wakes up, precisely for the reason that we do not remove the mentioned assimilate reserves. However, it is important to make the final cut only in the growing season, i.e. in flowering period, and even during that we use it in critical places, i.e. in the branching, when we want to take down an older shoot on a younger, thinner branch, a cut on the so-called Zahn’s stump, i.e. an active cone, which we remove until in the following years, when that branch becomes sufficiently strong. With stone fruits, it is especially important not to make large cuts, and even small ones are better covered with wax. It is also important to know that overgrown trees, whether cherry or plum, cannot be effectively rejuvenated.

The most common mistakes that are commonly made when caring for trees:

1.  Too radical rejuvenating cut – relegation to just the torso: As a result of the resulting imbalance between the roots and the above-ground parts, although the tree produces abundantly from practically all dormant buds, unfortunately even these lush shoots are nowhere near able to attract enough energy to flow throughout the entire volume of the skeletal branch. The lower half of the branch begins to dry gradually, and the drying progresses further towards the trunk. In the longer term, an invasion of wood-destroying fungi can occur and, overall, the tree becomes mechanically unstable, it is much more likely to break. In addition to the ruined state of health, the disadvantage of reckless rejuvenation is of course the loss of harvest for at least two years.

2.    Removal of the terminal (main top shoot) and the formation of a hollow crown: A very often seen phenomenon. As a result of the loss of the terminal, which acts dominantly on the subordinate branches, the tree loses any growth order. A lot of vertically growing shoots will come out that want to replace it. Whenever we treat a similarly felled tree, it is necessary to gradually remove these bayonets, because due to the unsatisfactory direction of growth, they cannot be used for rejuvenating skeletal branches. It is sometimes advisable to spread the removal of bayonets over two years, if there is a risk of the formation of longer deaf parts on the skeletal branches. However, it is advisable to remove the ones that we will leave. The removal of the terminal has another negative meaning, namely the formation of a so-called pool, down in the hollow crown. Even with the best dressing of the cut wound, it is impossible to expect in the long term that the wound will not start to heal. Water flows there from a large part of the volume of the tree.

3.    Shaving skeletal branches: also a common mistake. Instead of reducing the levers on the skeletal branches by dropping to a younger branch, the younger branches are pointlessly removed and the lever remains more or less identical. Fertility moves absolutely only to the perimeter of the crown, these trees can be harvested practically only by shaking them.

4.    Leaving stumps: A very common mistake. If we leave the stump inactive, i.e. dry, the wound cannot heal, the wood will gradually dry out and the necrosis will progress further into the trunk. During a corrective cut, the callus (note the healing tissue, formed during the regeneration of wounds after cutting off branches) is sometimes inactive on the part of the cut, so the wound heals much more slowly and unevenly. Dry branches in an unmaintained tree have the same effect as leaving stumps, the drying progresses to the trunk or skeletal branches. The rule of the so-called cut to the branch ring, or even slightly below it, applies, when the frayed edges of the wounds should be smoothed with a gardener’s flip flop. With a properly maintained tree, due to the even flow of energy, no branch should ever dry out.

5.    The issue of broken branches: It has less to do with poor maintenance than lack of maintenance. The uncut end of the branch can form a barrier in the outflow of water, in the horizon of several years it can rot into the skeletal branch. This is a frequent and completely unnecessary cause of a decrease in the mechanical resistance of many trees.

Author: Ondřej Dovala