Cutting the walnut tree: this is how it’s done!

In order to answer this question, it is necessary to mention some basic facts about the walnut tree – for a better understanding of the connections. Unlike most other fruit trees, the walnut is very sensitive when it comes to cutting. This is why you have to be particularly careful and precise in order not to harm the plant.

Exceptionally large amounts of tree sap emerge at the interfaces of the walnut. One speaks of the “blood of the tree”. The walnut tree therefore bleeds a lot more than its relatives. Anyone who has never dealt with a walnut is sure to be surprised or even shocked the first time when they see how much juice flows out after cutting.

When pruning, the main thing is to use a sensible strategy to ensure that as little tree sap as possible escapes. Otherwise, under unfavorable circumstances, serious damage to the fine piping system of the walnut tree can occur: If there is frost during the pruning or a short time afterwards, the sap freezes in the wounds. Then, unfortunately, tissue tears and other problems are already preprogrammed. In addition, pests and plant fungi have easy play due to the increased moistureAll of this means that the walnut must never be cut after the leaves have fallen – i.e. in spring or winter. Otherwise the scenarios described threaten to occur. Instead, the tree should be pruned in late summer, when it is neither sprouting nor in preparation for winter. A dry, sunny and warm day is perfect.

Different dates for different cuts

The time of late summer primarily refers to the so-called correction cut. In addition, there is also the plant pruning and the educational pruning.

Corrective pruning
For older walnut trees, corrective pruning is an elementary maintenance measure that requires a lot of know-how. It is important here to prune the respective tree sufficiently, but as little as possible. This is mainly because older generations are naturally more sensitive than younger trees. It is therefore advisable to carry out the corrective pruning in late summer between mid-August and the end of September and benefit from the fact that the walnut is less stressed during this time (due to the lower amount of tree sap that escapes).
Time:  mid-August to the end of September

Plant pruning
The plant pruning is used to give the crown a beautiful, adequate shape. It should preferably be carried out after the leaves have sprouted successfully. This is the case between mid-June and mid-July.
Time:  mid-June to mid-July

Parenting pruning
In order to promote the further growth of the walnut tree, a parental pruning is worthwhile. Like the plant pruning described above, it is best tackled on a mild day between mid-June and mid-July.
Time:  mid-June to mid-July

When nature interferes

In general, you can stick to the times mentioned and plan the desired or required tree pruning without any problems. However, every now and then nature interferes. In these cases you are forced to go to work outside of the usual cutting times.

But which situations are there that encourage the hobby gardener to act spontaneously?

A strong wind or even a hurricane leads to wind breaks. Sometimes it is important to quickly remove some of the large branches. However, this inevitably goes hand in hand with the release of large amounts of tree sap and causes corresponding damage.

A question of the right cutting technique

Before the individual prunings (corrective pruning, plant pruning and educational pruning) are described in practice, the fundamentally important and typical pruning technique should be briefly introduced: If you prune the branches of the walnut tree above the buds, this promotes the sprouting of the latter.

The correction cut in detail

The main goal of the corrective pruning is to remove branches that destabilize and deform the walnut tree. It is mostly used on older trees, but it may also be necessary to make a cut like this every now and then on younger walnuts.

But how does the correction cut work in detail?

In principle, you can use the basic technique described above – shorten the branches above the buds. Now the question arises, which shoots need to be worked on exactly. With a walnut tree, it is very often the case that side branches sprout steeply (grow at an angle that is too acute to the main branch) and compete with the “scaffold shoots”, i.e. the branches that give it shape. Such side branches are referred to in technical jargon as “slotted branches”. They are not stable with the main branch. As a result, they break or tear easily.And now the big problem that can arise from this constellation: If a walnut tree produces a particularly large number of fruits, it is difficult for the slotted branch to carry the load. As a result, it breaks, which in turn leads to dangerous lacerations on the trunk. The latter usually heal poorly and can promote further damage – in the worst case, such a scenario even means the death of the tree.

That is why it is so important to react with a corrective cut in good time. As soon as you see slit branches on the walnut tree, action should be taken. It is sufficient to remove these “risk drivers”.

Information on plant pruning

The whole point of pruning is to create the basis for a beautiful, lush, high-yield tree canopy. In order to be able to do it properly, one needs some background knowledge about the growth of a walnut tree. In the first two years, the plant mainly grows on its main cane. The side branches do not shoot until the third year.

Before doing this, however, minor pruning work is definitely permitted: With a young tree, it is advisable to ensure that the trunk is straight and that there are several annual side shoots. If you plant the tree in spring, you have the option of making minor adjustments (if necessary) in the same year (i.e. in late summer). If the tree is planted later (in summer or in autumn), you have to wait until the following summer.Instructions for planting pruning:

Step 1: Establish four scaffold shoots – a vertical central shoot plus three side shoots that protrude at an angle of 45 to 60 degrees to the main trunk.

Step 2: First leave the scaffold shoots alone, completely remove all other shoots.

3rd step : Slightly shorten the side shoots – stronger ones by a third, thinner ones by half their length.

Tip: To ensure that new shoots grow outwards and not into the inside of the crown, you should make sure that the upper bud points away from the trunk.

4th step: Shorten the middle shoot so that there is an angle between 90 and 120 degrees between the individual side shoot tips.

The procedure ensures that the growth of the walnut tree is fully concentrated on the scaffold shoots. The aforementioned angular position of the main shoot in relation to the side shoots promotes the uniform development of all scaffold shoots.

Everything you need to know about the upbringing

Unlike most other fruit trees, the walnut usually does not need a parenting pruning. This is only necessary if there is a risk of incorrect growth. It then contributes to an evenly growing crown.
The procedure is simple: After the leaves have sprout, all the steeply growing branches and the shoots that compete with the framework must be removed. In addition, scaffolding drives of different lengths can be adjusted to one another by shortening the longer ones.

Important: If individual branches sprout directly from the trunk, they should be removed as soon as possible after sprouting.

Extra: tenoning – yes or no?

As a rule, you cut off the unwanted shoots on the astring, but the walnut is particularly sensitive to this, especially if it is cut very close to the trunk. The resulting wounds dry out over a large area and can also affect the main shoot as a result. For these reasons, tenon cutting is of great importance in the walnut tree. The method is intended to counteract the dangers. Specifically, it is about always leaving a tenon when cutting. Although this dries out from above, the lower part remains alive and able to continue to develop new shoots.

After a few years you can finally remove the cone that has dried up in the meantime. It is important to ensure that you saw off the tenon slightly downwards and outwards at an inclined angle. In this way, it is removed without damage, which means that there are no wounds on the scaffolding. In addition to the many proponents of this method, there are also opponents who identify cones as foci of putrefaction and, as a result, as entry points for diseases.

You therefore advise making the cut close to the trunk (on the astring), but not parallel to the trunk (due to the risk of large wounds). In the end, both variants have their pros and cons. The hobby gardener has to make a decision and then simply observe how the chosen method “works” and intervene if necessary.

How to best saw off thick branches

If you want to thin out your walnut tree, you can sometimes not avoid sawing off thicker branches. It is now clear that these branches are very heavy. If you proceed carelessly, it can quickly lead to cuts or tears that heal poorly.
In order to prevent this, an adequate, gentle technique is needed:

1st step: Saw the branch to be removed on the underside up to the middle.

Step 2: Repeat the same on the top of the branch, but a few inches further from the trunk.

As a result, the dead weight of the branch ensures a uniform breakthrough. The trunk is not damaged in the process.

Step 3: Remove the remainder with the saw. After the preparatory work, this succeeds without any effort. The only important thing is not to damage the astring.

Soon after the branch is completely removed, a healing layer of cambium covers the wound.