One of the most important reasons for pruning walnut trees is to encourage fruit production. But this is not unique, since other purposes of pruning are to facilitate harvesting, direct tree growth and formation, improve ventilation and facilitate sunlight penetration. Young walnut trees are pruned in their first years to determine their structure. Tree shaping is critical as it affects crop quantity and quality, ease of harvesting and other agricultural activities. A lot of people don’t know how to prune a walnut tree.
For this reason, we are going to dedicate this article to telling you everything you need to know about how to prune a walnut tree, when to do it and what aspects to take into account.
Contents
nut size
Pruning mature walnut trees to maintain their structure and clean the inside of the tree improves sunlight penetration and ventilation inside the plant. All of these activities benefit the production of nuts in future harvests. The pruning of mature walnut trees is done annually or every two years.
When it comes to pruning walnut trees, certain criteria must be taken into account. If there’s anything we need to consider when planning walnut tree pruning, it’s the frost forecast after pruning. Like other fruit trees, Walnut trees can suffer tissue damage if frost occurs after pruning. So, whenever there is a risk of frost (temperatures close to 0 degrees), pruning should be postponed until the risk disappears.
Therefore, it is always necessary to try to align pruning with the dormant periods of the tree. Generally a good time to prune a walnut tree is it late winter or early spring, before the tree becomes active again, if frost is not expected. This will reduce sap loss and as the growth phase approaches, the wound will soon begin to heal. In climates with slightly cooler winters, fall pruning may be a good option.
While major pruning, such as formation, production, or regeneration, should be done in the cool season, green pruning is not. A good time to green walnut trees is early to mid-summer, when it’s hottest.
what tools do i need
To learn how to prune a walnut tree, you will need several tools, depending on the size of the tree and the type of pruning you want to perform. Here is a list of some walnut pruning tools:
- One-handed pruners: Can be used to cut branches up to 2.5 cm in diameter. These scissors are more recommended for cutting greens.
- Two-handed scissors: We can use it to cut branches up to 5 cm in diameter.
- They are used for sawing branches from 5 to 20 cm in diameter. For large branches and trunks we will need a chainsaw.
- Chain saw : They are used to cut thick logs over 20 cm. There are electric chainsaws and gas chainsaws that use batteries or power cords. This is the name of the scissors, saw or chainsaw with telescopic handle that can reach the highest branches. With these tools we can cut branches at a height of about 5 or 6 m.
- Stairs: It is important to respect the safety rules and not to swing at the top of the ladder. Remember that you have to go down a few steps and your height should not exceed the last step. In such missions, falling from heights is dangerous.
- Security elements such as gloves, glasses, equipment, boots… remember to protect yourself and work in complete safety.
- It is recommended to sterilize the knives before cutting them. This will help prevent fruit tree diseases.
How to Prune a Walnut
To prune a walnut tree, you must first know the type of pruning you are going to do, and for this you must know the age of the fruit tree. Pruning a young walnut tree that is growing and needs to be trellised to prune it is not the same as pruning an adult walnut tree, you will have to think more about production and enhance the harvest.
How to prune a young walnut tree
Young walnut trees require training pruning to establish a central axis for the growth of the rest of the tree. We can say that a walnut tree is young when it is less than 5 or 6 years old. This is relative, since the trees vary more or less according to the region, the climate, the variety…
Pruning during this growing season is intended to guide the tree’s growth and define its structure. We will see the type of pruning we need to perform at this stage of development:
training size
This includes directing the structure and growth of the tree during the early years. Since this is a fairly vigorous pruning, do it when the tree is still, i.e. in early spring, or in autumn in regions where the winters are not too cold. Cutting the tree formation is done as follows:
- During the first year, prune all the branches of the tree to promote germination lower branches.
- The main branch appears in year 2. We leave the lower branches, except those that grow from the lower half of the trunk.
- In the 3rd year, we can the main branch to 2/3 of its length and remove the branches which pushed into the cut at an open angle.
fruiting size
Its purpose is to establish secondary productive branches. It’s about choosing the 3 or 4 main branches where you want the rest of the tree to grow. The slope of the main branch should not be too high to prevent it from breaking under the weight of the crop in the future. In this way, we will prune the suckers that grow from these branches, we will cut them a little to about 2/3 of their length, thus establishing the structure of the tree.
How to Prune a Mature Walnut Tree
Trimming a mature walnut tree to maintain its shape and clear the interior of the tree promotes ventilation and light inside the canopy. This is called production pruning, although rejuvenation pruning and green pruning can also be done at this stage.
production size
This pruning is done to take advantage of the amount of sunlight captured by the crown, maintaining its shape to improve the quality and quantity of the harvest. It consists of cleaning and thinning the branches to facilitate the entry of light and facilitate fruiting.. Split cups are preferable to spherical cups because they increase the display surface, making the most of the light. Unproductive branches or suckers should also be removed, as well as side branches growing inside the tree.
As we said, with all this, in addition to ensuring a better quality fruit, the yield of the trees has also been improved. We will proceed as follows:
- First, we will remove the biggest suction cups, because they are not very productive and suck the sap from the branches from which they grow.
- We will leave the weakest suckers or buds inside the tree to shade the structure of the tree.
- The lower branches should be pruned because they receive less light and therefore bear less fruit.
- The cut should be leaf-shaped with many entrances and exits to Increase exposure and make better use of light. We will also remove branches with very sharp angles.
- To maintain the leaf/wood ratio, thinning of the twigs should not be carried out too intensively. Therefore, we will avoid excess wood, which reduces regeneration and the formation of productive branches.
rejuvenation waist
Rejuvenation pruning, also called renewal pruning, is performed on trees that show signs of aging after a long period of production (20 to 40 years). These symptoms can be:
- small leaves
- yellowish color
- loss of leaves inside the tree
- low production
It is an energetic pruning that rejuvenates the walnut tree, although it can also be done gradually.
- Substantial rejuvenation size: In the first case, we remove all the leaves from the tree, effectively leaving the base and the main branches of the trunk to grow back.
- Gradual rejuvenation size: It consists of pruning from the top of the crown to the base of the branches. This is done in stages, every 3 years we will cut one of the four main branches of the tree.
green size
Renovation pruning or green pruning can be practiced in summer. Although it can be done at any time of the year, it is usually done at the end of August, when the walnut trees have little activity due to the heat. This is done to control the growth of suckers or root suckers, removing those that are unavailable to walnut trees.
What do we do with pruning leftovers
After the pruning is done and all the work is not done, we still have to remove the remains of the branches. But how do we treat them? … well, we have a few options:
- Use a tree chipper. This type of machine makes our life easier and is also ideal for enriching the soil with organic matter since the crushed material can be spread on the ground. Today, a household shredder is available in any pocket in the market.
- burn the branches. To do this, we must apply for a permit at the town hall where the walnut grove is located. Some days fires are not allowed, so we had to inform ourselves in advance and ask for the corresponding permits.
- To make firewood for stoves, ovens, fireplaces, etc. To do this, you need to prepare the remains of branches and trunks, chop them and make small pieces, remove the leaves and sprinkle them on the crops. For example, this wood can also be sold to companies that need a wood-fired oven, such as bakeries, pizzerias, etc.
Hopefully with this information you can learn more about how to prune a walnut tree and what you need to consider for it.