Today we face a technical issue that is close to the heart of many fans, the olive tree pruning.
The olive tree is undoubtedly one of the most common trees in our countryside and has always been linked to our territory. Proper pruning operations are one of the essential aspects for the rational and productive growth of this tree. Prune the olive tree correctly it allows you to have a good amount of fruit and maybe produce an excellent one on your own extra virgin olive oil.
So let's see, in this article, the different ones forms of olive grove farming. And how they are articulated in the different periods olive tree pruning interventions, trying to give an indication of the different phases of the long life of this precious tree.
The olive tree, scientific name Olea europaea, is one of the oldest fruit plants used for human nutrition. It is native to the countries bordering the Mediterranean and belongs to the botanical family of Oleaceae.
It is a very long-lived tree, which goes through different stages of life. The rearing phase, after planting, lasts about four years.
From four to eight years old, if the plant has been well cared for, irrigated in the driest periods, fertilized with green manure, pruned properly, the first production phase begins. The productions are then increasing over time.
From 8 years on, the olive tree begins its maturity, which lasts about 40-50 years, where production stabilizes. Aging begins from 50-60 years onwards. In favorable soil and climatic conditions the plant can age for hundreds of years.
The root system of the olive tree is quite superficial, usually not going beyond one meter in depth. The roots, however, extend very horizontally.
The tree has a cylindrical trunk, gray in color and twisted in shape.
The olive wood it is one of the best ever, as it is hard and heavy.
At the base of the trunk, called stump, numerous basal suckers are generated every year, which must be eliminated using the right tools for pruning.
The olive tree is an evergreen tree, with a continuous vegetative activity that slows down only in the winter period. The leaves appear on the branches in the opposite way. They are elliptical in shape, are leathery and have a small petiole. The lower page is silvery-white, while the upper page is usually green. The buds, from which new branches are generated, are of two types:
Gems can also be:
The hermaphroditic flowers are small, white in color, grouped in cluster inflorescences in a variable number from 10 to 15. The tree emits its inflorescences, called little fingers, on the axils of the previous year's branches. Depending on the climatic zone, the inflorescence begins between March and April and. Depending on the variety, flowering starts in May and ends by June at the latest.
The fruits, which we all know, are olives: globose drupes, of different shape, color, size and possible uses depending on the variety chosen. It is a very important drupe for the Italian agricultural sector. Only in Tuscany are there at least 79 native varieties. More generally, many Italian varieties appear in thelist of dop products.
Let's immediately dispel a false myth, namely that if the pruning is not done, the olive tree will not produce.
This is not true. Indeed, in the olive tree cultivation pruning is also very important in this sense.
What is true is that a well pruned olive tree it increases its production and makes it easier to pick the fruits. In fact, the first problem that arises when faced with a olive tree not pruned is the one related to the collection.
The olive tree is a plant that tends to grow upwards in free form. So imagine a plant of 8 meters. Taking the drupes, in such cases, as it is easy to understand, becomes expensive and difficult.
To harvest the olives, when we talk about limited productions, we can proceed by hand. But much more convenient is the use of manual shakers or harvesters (which you can find here), which usually reach a height of 4 meters.
Collecting in this way, we have a best quality olive oil, because we collect the green drupes, when they are still at the plant. It is true that some believe that the beneficial properties of extra virgin olive oil are all still to be demonstrated.
If recovering the fruits, due to the height of the tree, is difficult, you have to wait for the olives to fully ripen and fall on their own to the ground. In this way, however, the drupes risk being damaged and compromising the quality of the oil.
Hence, the objectives of olive tree pruning I'm:
The olive tree pruning interventions vary depending on the life stage of the tree. In the first few years, as the plant grows and takes its shape, they will be very contained. In the adult-juvenile phase, when the production is at full capacity, a medium intensity pruning will be provided.
In the period of tree aging, when the phenomenon of production alternation is stronger, more incisive pruning will be carried out.
Depending on the period of the year in which action is taken, we distinguish two types of olive tree pruning:
Let's now see the different operations to be performed during olive tree pruning.
The so-called "breeding" is the first olive tree pruning operation. Often this type of intervention is done in the nursery.
With the breeding pruning the future shape that the tree will have to assume is set on the young plant.
Among the different forms of olive farming, that a polyconic vase it is among the most widespread. From the stem of the plant, which is cut (deck) to a height of 100-110 cm, 3 or more main branches are branched out, which will give the tree its final shape. The polyconic vase shape is a setting that allows excellent aeration of the foliage, avoiding excessive thickening of the vegetation.
To the breeding pruning follows the training pruning, which serves to better impress the desired shape. This is done by eliminating the shoots of the plant under the scaffolding point, which could interfere with the planned training system.
Another form, but less used, is the bush. This shape is obtained by not practicing any type of pruning for the first 8-10 years of the tree's life. An exception is the thinning of the small basal branches in the first 50 cm, to be carried out after the transplant or at the end of the first year.
When the plant is developed, a globoid shaped bush with various buds is obtained. This is contained in height, with more or less drastic pruning from 10 years onwards. In this way, a shape is obtained that is very similar to the one that the olive tree would have in nature. Periodically necessary pruning with this form is the cutting in turn of the trees of the entire plant.
Similar to the bush is the shape of globe breeding, with a scaffold that is carried out at 60-80 cm. from the ground. The branches develop from this height without an established order, reaching different heights with the branches. Observed over the years, the plant assumes a globular shape.
There are also low breeding forms, such as the bushy vase, which is obtained either by scaffolding the plant at a height of 60-70 cm from the ground, making 3-4 branches tilted outwards, or by using 3-4 plants planted at a close distance, not more than one meter one from the other. The plant is kept low with subsequent pruning, which favors branches outwards and not upwards.
Finally to remember the form of monocone farming, much easier in pruning operations.
To set up the plant with this form of training, training prunings are carried out, in the first two years of life, in order to eliminate basal branches in the first 90-100 cm. In the monocone the main branches are distributed in the shape of a helix along the trunk. They have a decreasing length starting from the bottom up. The top, in fact, is very lightened to avoid shading the lower part.
In general, all breeding and training pruning interventions are carried out during the dry or winter pruning period.
With the pruning of the production olive tree, we intervene on the adult plants, with different purposes. The main one is to renew the fruiting branches, by completely eliminating or shortening a certain number of branches. This serves to limit the competition between the branches themselves within the canopy. Production pruning is carried out both in winter and in the spring-summer period. In the first case, the operations of lightening the foliage and the tops are carried out with the return cuts (dry pruning). In the second case, the basal suckers and suckers are eliminated (green pruning). Keep in mind that the olive tree bears fruit on the branches of the second year and that suckers can be eliminated even in winter.
The fruiting branches are the toast it and the mixed branch, while on wood that is two or more years old, the vegetation is lost, as there are no normal vital gems. At the same time, however, despite the old wood, the plant rebalances itself, because it is able to emit new hunts from the latent buds.
In the mixed branches, on the other hand, the terminal buds and the first pairs of underlying buds develop into wood. The branch, continuing to grow, begins to weigh and fall down, forming the so-called gutters, the best bearers of fruit.
At the maximum point of curvature, the gutters emit new twigs. Some of these twigs will be removed, others will be used to replace the same gutter when it is exhausted or stretched too much.
In the olive tree pruning operations for production, these peculiarities must be taken into account, which allow the gradual and periodic rejuvenation and rapprochement of the fruiting branch of the mother branch.
As for the suckers, however, they are sometimes left and then go to replace old or damaged branches.
With a correct production pruning, the objectives of a better distribution of vegetation on the plant are achieved. Furthermore, the chosen form of cultivation is maintained and the formation of new fruiting branches is stimulated.
Others olive tree pruning operations they are those of reform or rejuvenation. These are done when you want to change the shape of the tree or rejuvenate it because it is too old.
In this case, vigorous cuts are made, always in the winter period. These cuts are used to eliminate one or more branches, depending on whether the goal is to restore the plant's training form, or to rejuvenate it.
In these cases the old branches can be replaced with suckers, and in the most difficult cases also with suckers.
These can be extraordinary operations, made necessary due to natural events such as a fire or severe frosts.
Slupatura, or, is also part of this type of operation pruning of rimonda. This pruning is aimed at eliminating dead wood or heavily damaged by diseases, such as luppa or olive caries.
Rejuvenating or rejuvenating pruning is a very tiring operation, which takes time to give results. Furthermore, more interventions are needed to be done in successive phases. In the end, however, this technique will give the olive tree a second youth.
In one of our previous articles, we made an extensive overview of the best tools to be used for pruning. For the proper pruning of the olive tree we suggest you take a look at the article. Remember that saws, hatchets and scissors must always be very sharp.
Another suggestion is to carry out the pruning operations when there is no danger of rain. It is also important that on larger cuts we intervene by dealing with Bordeaux mixture (allowed under organic conditions) is special mastics. This foresight allows to avoid the risk of infections for the tree.
Finally, we recommend that you use great caution when you are forced to climb the tree to make the cuts. Falls from olive trees are among the most frequent accidents that occur in our countryside. Better to use some special aluminum ladders, light to carry and that can be properly anchored to the ground, rather than venturing (with hands full) in situations of precarious balance.
Organic Cultivation is a blog that was born from our desire to spread the good practices of organic farming. To do this we decided to give our knowledge to anyone who wants to get involved and create their own vegetable garden (even using a terrace or a simple balcony). Growing without the use of pesticides is possible and we want to prove it by presenting alternatives biological and effective for any type of problem linked to agriculture.
The olive tree is an absolutely loved plant, not for nothing has it earned the nickname "rex arborum". We love the beauty of the olive tree, its foliage, its shape, its fruits, the oil, the resulting products (cosmetics, soaps) and its peculiar and unique wood. The greatest professors and scholars have dedicated monographs and entire volumes to this plant. Even today many of its vegetative and physiological aspects are not explained. Perhaps the reason for so much interest is due precisely to the fact that many of its aspects still remain a mystery.
The olive tree is a Mediterranean species and is directly linked to the cultural, social and economic history of all the populations that have developed there since time immemorial. Despite the thousands of varieties existing in the Mediterranean basin, every olive grower, from whatever region he is, knows that he risks a quantitative loss of production for various reasons. If we exclude the errors of fertilization and pruning (still many do not fertilize and many have learned to prune by "hearsay" or "having seen it done") the main scourges that cause huge losses of olives are due in the first place to the fruit fly. olive tree (Bactrocera Olea) followed by, in order of importance, Cycloconio (also called Peacock's eye, the agent is the Spilocea Oleagina fungus), olive moth, other insect (Prays Oleae) and olive mange (disease of bacterial origin). Mange, in addition to decreasing the amount of fruit due to tissue damage, affects the aesthetic appearance. The name of the pathogen is the bacterium Pseudomona Savastanoi pv Savastanoi, which takes the name of the researcher who first scientifically described and studied this disease. The professor. Luigi Savastano in the volume "Tuberculosis, Hyperplasia and tumors of the olive tree", Tipografia Ferrante Naples, 20 September 1887 and later in Lessons of Applied Tree Pathology of 1910) declared that this pathology was of bacterial origin. Savastano was also the first to inoculate the bacterium in healthy plants. He also managed to isolate it from the tubercles.
Olive mange is the pathology considered in this article because many of us still do not know how to eradicate it and try in vain to make it disappear from olive trees. Through knowledge and culture we can understand the functional mechanisms of the disease and only then act correctly, much more simply than you think, to keep the level of bacterial load low. Initially this pathology was mentioned for the first time by Theophrastus of Heresus (about 287 BC) and later by Pliny the Elder (50 AD, who reports as described by Theophrastus). Many later began a description of the tubercles but in a very approximate way for the most part descriptive (the Targioni-Tozzetti, the Giovene, the Moschettini, the Presta, the Tavanti, the Carradori, the Ridolfi, the Cuppari and the Caruso). Only Savastano took a scientific approach discovering that the cause of this disease was of bacterial origin. The olive tree is not the only plant species sensitive to the disease but so are many other oleaceae (such as privet, ash, jasmine, oleander but also myrtle). In the following we will see how to restore plants affected by mange to health and how much the hand of man through pruning influences the spread of the same.
Not all varieties are sensitive to olive mange. Varieties (cultivars) change from region to region and among the varieties some are more suitable than others to show symptoms and to ensure that bacteria, once they have penetrated into the tissues, begin to proliferate. There is a sensitivity scale, referred to olive trees, which goes from high to medium to low and anyone who owns at least one olive tree will be able to realize by himself, through simple visual observation, whether this or that olive tree is more or less resistant. to the attack of the pathogen.
Among the most sensitive varieties we find the Frantoio in Tuscany, the Moraiolo in Umbria and Tuscany, the Corregiolo in Emilia, the Razzola in Liguria, the Ogliarola del Vulture in Basilicata, the Cerasuola in Sicily and so on. Among the most resistant we have Leccino, Nera di Oliena in Sardinia, Ogliarola Salentina in Puglia, Ascolana Tenera in the Marche, Itrana in Lazio, etc ...
Once we understand what has been said so far, it will logically be understood that possessing sensitive varieties implies, as much as it may bother us, that our plants will always be subject to manifest tuberculosis expressing more or less large areas of infected tissues.
The bacterium is of the epiphytic type (which means that it lives on the foliage of plants). More precisely, it lives on tree branches and nestles on the underside of the leaves. It does not live underground and has a very short life on the ground. From these first characteristics it can be deduced, just as logically, that bacteria do not live and consequently do not propagate through the roots as well as they will not colonize the various parts of the olive tree crown starting from the soil. Therefore, if we leave infected branches on the ground, the bacteria present will not spread from them towards the crown. Instead, being present all year round on the branches of plants, it will be necessary to look for the source of the inoculum there.
On soil and in the soil the bacterium has a short life (3-10 days). In the olive tree and other oleaceae such as privet, there may be characteristic tubercle formations at the point of infection but also peripheral locations of cancers due to systemic propagation (through lymph and wood channels). Numerous works explain what are the ways of spreading the disease. Over the years, as many molecular investigations have been carried out in order to isolate the various strains of Pseudomonas Savastanoi, to better understand their propagation mechanisms but also to understand what were the reactions of the olive tree during the various stages of cancer development. Various analyzes show that the formation of infected areas is related to the production of indolacetic acid and cytokinins in the diseased areas. Diseased areas are also encountered near the primary area, the bacterium therefore has an invasive capacity, that is to metastasize and propagate systemically (enter the circulation through the lymphatic ducts) (Penyalver et al, Phytopathology, 96: 313-319, 2011) .
Cancers in the "juvenile" phase are light brown tending to greenish and have a fairly smooth, not very rough appearance. Inside, the tissues are of the spongy type. As we age, the tubercles grow in size and diameter and take on a dark brown color. They look similar to cratered half balls. They are made up of necrotized tissues on the outside, similar to more or less large crusts joined together with obvious furrows.
The bacterium cycle is very simple. Pseudomonas Savastanoi remains inactive on the plants and on the lower pages of the leaves until the ideal conditions arise and does not find a way of access inside the plant. The periods of greatest infection are autumn and spring.
Propagation occurs with water droplets and humidity. Diffusion takes place not only between the various areas of the plant but also in the olive grove, from plant to plant. If we have healthy olive trees, Pseudomonas Savastanoi will live without causing damage but as soon as some external element causes any injury to the host, it will settle and find a way of penetration to be able to multiply later. It is good to know that Pseudomona Savastanoi can also penetrate through the stomatal openings and create chambers inside the leaves (substomatic chamber, substomatic chamber). It is no coincidence that the periods of major infections occur during the months of October / November and around March / April which are also the times for harvesting and pruning. The hand of man is not the only originating agent because the fall of senescent leaves or leaves affected by Cycloconio (or peacock's eye), hailstorms as well as the damage produced by insects or birds can create entrance doors to the underlying tissues.
The activity temperatures of Pseudomonas Savastanoi are between about 5 ° C and 40 ° C. This makes us understand that the bacterium can penetrate into open wounds, if the conditions allow it (as already mentioned, for example in rain). Obviously the ideal temperatures are never those that are located at the extremes and but around 22 ° C-25 ° C. The infection does not cause immediately evident and visual damage to our eyes but manifests itself the following year. So, to see or not the areas affected by the bacterium we will have to wait until the following spring. I would like to emphasize that the aggressiveness (and penetration) index is directly proportional to three parameters which are, a) the presence of wounds, b) high humidity, c) temperatures around those listed above (22-25 ° C). The concomitance of these three factors is the best situation for the proliferation of the disease and the worst for the olive grower. In conclusion, ABSOLUTELY AVOID working on the olive tree with the risk of creating injuries if you are in the presence of susceptible varieties and the presence of factors b) and c).
Never has a plant divided experts more than the olive tree. From North to South, in fact, times, ways and even "designs" change that are given to him. This is because each olive growing area takes into account the land, climate and cultivars, the age of the olive tree and its possible response. From these elements, a certain “pruning system” derives. They all have in common thebe careful not to grow branches inside the plant, letting light, air, sun and even birds pass through it. And all methods aim at distribute the fruit production on the branches and favor the growth of the plant especially in the period in which the production is less abundant. However, we must consider that each plant "responds" in its own way and therefore it may happen that the pruned olive tree to rejuvenate its foliage also requires other "return" cuts in subsequent periods, so it needs to cut other higher branches that replace others destined for a greater production of olives.
To avoid problems and imbalances in the distribution of plants and avoid disastrous pruning, we will briefly explain how to do it to distinguish male plants from female ones:
Female kiwi plants are the ones that produce the fruits and have yellowish-white flowers of about 4-5 cm gathered in clusters spaced apart to favor the development of the fruits.
Male plants, on the other hand, exhibit smaller flowers and gathered clusters dense and very close to each other.
They exist essentially two approaches to prune trees ad tall trunk, those that actually present more problems of a practical nature.
The first is to call a firm that makes use of mobile crane or aerial platforms, to reach the higher branches. In general this is the most used method.
However, interventions with pruning professionals who operate thanks to theuse of ropes.
The techniques used are practically identical to those used for the tree-climbing which allows notable advantages to the client:
minimal disturbance for any neighbors
possibility of reaching trees in very inaccessible areas
elimination of cranes and platforms with consequent savings on prices
even the pruning of the highest branches will not be a problem.
The firm Rope Access among other things, also pruning trees on rope. Interventions of this type can be fundamental for the pruning of trees in the cities, especially in very narrow streets or through trees inside condominiums where a mobile crane could not operate.
The right time to prune kiwis is February , at the end of winter and before the arrival of spring. It is the best time to pick up the shears, because you can promptly intervene on the branches that have already given fruit (and must be eliminated) or those that have been damaged by frosts and winter disturbances.
The purpose is to lighten the plant , stimulate it to produce bigger and quality fruits and prepare it in the best way for flowering. There are those who argue that kiwis live in parallel with vines and that they should be pruned at the same time: this is true but not entirely, because technically the life cycle of a kiwi branch is slightly longer (it can bear more the weight of the buds).
A second pruning can be done in the month of May : the buds will have proliferated a lot from the first pruning in February and for this reason late spring is the best time to eliminate all that is in excess to concentrate the kiwi plant towards targeted, productive and fruitful growth.
The pruning of male and female plants also differ according to the right time to prune the branches: it would be preferable to prune the male plants in late spring, after flowering, while the female ones at the end of winter, before flowering. Finally, tradition would have it that the pruning operations were carried out in the phase of falling moon .
Aside from the remedies described above, there are many specific products for disinfection of the shears.
Some can be found for sale at nurseries or specialized centers. The best are the ones based on chlorhexidine, one element, which eliminates many bacteria which can be harmful for plants.
Before buying them, however, check that these products are free of products chemists which can be harmful for the environment.