Train and Shape Olive trees, Maintain or Increase Production and Improve Harvest Efficiency
by Marcelo Berlanda of The Olive Centre Agronomy Services
Training olive trees help give the tree the optimal shape to allow for efficient harvest as well as achieving early olive crops.
Once the olive trees have reached their optimum canopy volume for the environmental conditions of the area, it is likely that the olive fruit yields could start declining. This is due to the fact that the inner part of the canopy does not receive sufficient sunlight, which causes olive leaf defoliation, resulting in a low Leaf to Wood Ratio.
If the tree grows above its optimum size, it creates serious issues for mechanical and olive harvesting machines. The tree becomes too high and too wide for the machines, it has thick branches that can cause damage on the picking heads and also reduces the removal efficiency of the harvesting machine as well as slows down the speed of your harvest.
It is a fact that to produce fruit, Olive trees need to grow and produce new branches each year; therefore the trees need to grow every year! It is here where pruning becomes a very useful management tool when growing olives.
Pruning helps increasing Fruit Size, Oil Yield, Light Interception and Leaf to Wood Ratio, it promotes new growth, and reduces water and fertiliser requirements.
1- Tree Training
Objectives: Achieve early start of olive production with higher yields, increased number of production years, higher fruit quality, prepare the trees for the type of olive harvester that is going to be used at the grove.
Training takes place during the first 3 years of the olive tree life.
During the first year minimum pruning is required (provided the trees come with a suitable shape from the nursery), lower and vigorous branches competing with the leader should be removed. The aim is to encourage a straight vertical trunk with horizontal branches coming out. Water shoots or suckers must be removed to stop competition for water and nutrients.
On the second and third year the aim is to remove lower branches below 600-700-800-1000mm (must be done gradually).
“Always keep in mind that if we prune too hard is because either we came too late or because we do not know what to do”.
There must be a balance between what is taken out and what is left on. If we remove too much canopy, we have a negative effect on the tree, because we are removing photosynthetic area setting the olive tree back for a while until it starts growing again.
Light pruning is a process by which we only take a small amount of foliage (a couple of small branches), therefore we are not affecting tree balance. That is why it can be done from August until the end of May.
Heavier pruning, in this process, we take a large amount of foliage therefore we are promoting a stronger reaction from the tree, this makes it susceptible to frost damage. That is why we should be delaying it until the end of September unless the weather is warmer. If that is the case we could start pruning olive trees at the beginning of September.
Tree training not only involves light and heavy pruning but also tree tying and skirting.
2- Production in olives
This type of pruning is performed on mature trees once they have reached full size. It has the aim of balancing the olive tree to obtain uniform and constant production every year.
As we all know when olive trees are young there is a larger number of non-productive branches and that is because those branches are actively growing, but once they have reached their potential, they stop growing and start producing fruits, after a while those branches are exhausted and they stop producing, therefore they should be removed, to encourage new growth and renew the olive tree.
If flowering or bloom is light, pruning can be confined to non-productive parts of the olive tree, preserving as much bloom and potential olive crop as possible. In years of heavy bloom, pruning can be more severe without excessive crop removal.
Time of pruning: bud break until early December.
3- After Olive Harvest (Cleaning)
The aim is to clean up the large broken branches that are left after the olive harvesters have gone through the grove. We could avoid it by spraying the trees with copper after harvest and wait until spring to take the damaged wood out.
About Mechanical Pruners: Collard Mechanical Pruners
About Harvesting Equipment for olives: OLIVE HARVESTING
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