Olive harvesting, the role played by mechanization
The use of mechanical means is the evolution of a strategic way to decisive increase the productivity of the crop. There are now many cultivars adapted for the proper use of shakers which assure maximum yields
European olives (Olea Europea) are a par excellence Mediterranean symbol established throughout history for all the peoples in the area. After originating in oriental regions they spread through the Mediterranean area thanks to the work of Phoenician and Greek navigators but it was the Arabs and Romans who spread the cultivations which now account for some ten million hectares and the production of about 850 million trees. From the time of the Roman Empire olive harvests have been carried out by hand for which ladders were used when needed. In our time this manual labor method has been rather wasteful, leading to the reason for aiming at a degree of mechanization for increasing levels of harvesting which must be capable of safeguarding as much as possible the quantities of the product as well as the arboreal heritage where the harvest is at work.
In Italy, as through the entire Mediterranean, there are a large number of predominant or exclusive olive grove enterprises and many small-medium detached businesses. The smallest of them are family enterprises which often use medium or small levels of mechanization, whereas those which are medium-large often rely greatly on workers in manual labor for the harvest with a high level of mechanization. Moreover, nationally there are large numbers of small or small-medium farms with lands of less than one hectar which almost always means the arbreal heritage is very obsolete. In general, harvesting is still one of the main expenses in the olive balance sheet. This impact varies on average from 25% to 50% of the total production cost of oil from the traditional cultivations, or dealing with olive trees hundreds or thousands of years of age where few or none adapt to harvesting performed big harvesters.
Though today harvesting conducted with manual labor has been abandoned - except for rare premium varieties for canning industries - now there is reliance on small harvesting machines such as olive comb-shakers introduced in the mid-1970s or machinery with much higher productivity like vibro-shakers mounted on tractors, telescopic or excavator lifters,
Even more recently, modern self-propelled harvesters based on grape harvesters have appeared on the market but specific planting layouts are required for them. Another obstacle limiting the evolutionary process in the sector is the layout of the plantings, The layout of the olive stands still insist on steep land areas were tractor access is difficult.
The Harvesters
In these cases it would be advantageous to move to different types of small backpack harvesters which, compared to traditional manual labor, are able to strongly increase the productivity for the operator. Now available on the market are models differentiated by type of power, internal combustion engines, battery electric motors, pneumatic, and harvesting components and length and by configuration and materials used like poles and other work tools. Also to consider is that these machines carry very low prices which means that a single farm can acquire more than one for use by several workers harvesting at the same time. The harvesting capability of every worker is increased by 30-35 Kg/h with a traditional harvest coming to more that 150 kg/h. Another significant a point is that a percentage these machines almost always pick the olives up to 98%. The selection of a machine must make sure it has an anti-vibration grip for lowering vibrations down to a minimum and that the frequency of vibrations can be varied to use the optimum level for the diameter of branches. In some areas, such as north of Bari, mechanization has become intense, more elevated for the strong presence of specialized medium-large olive businesses with widespread cultivars suitable for the use of mechanical harvesters mounted on tractors, telescopic and excavator lifts. A basket fixed to the top of an articulated boom is wrapped around the tree at the base of the trunk and then an upturned umbrella is opened with hydraulics to intercept the olives dropping which are sent onto the basket by hydraulic poles. This is a solution which makes it possible for a single operator to harvest the entire yield of the trees in a few minutes, including the full regime, or close to it, the hookup and discharging the product harvested. In this case, with most favorable conditions, a single operator can bring in a yield of more than 2 t/h. The baskets and umbrellas of this equipment can take on different shapes and diameters to adapt them to the olives and the single tree trunk, whether brushpot or centuries old.
In past epoches it was advised to not work on trunks with stratum basale greater than 50-60 cm due to research conducted by important southern Italian universities which were able to optimize the intensity and frequency of vibrations transmitted to the tree for limiting damage to a minimum. Now these machines can be used profitably even on trunk diameters of more than 1 meter and recent experiments have underscored the importance of taking the geometry of the tree into account. Maximum efficiency for the worker does not depend on the weight of the olives or the resistance of picking the fruit but what does count is the configuration of the tree and the branches. In this setting, Leccino, Frantoio, Maurino, Nostrale di Rigali and also S. Felice, la Dolce Agogia and Pendolino have a good attitude for harvesting mechanization and have achieved results which are more than acceptable with adjustments for the frequency of shaking. On the other hand, the unique Moraiolo cultivar not very suitable for mechanized harvesting.
Olive cultivation in Italy and the Mediterranean
The region with the greatest density of olives stands in the world is Andalusia which accounts for 80% of Spain’s production. Italy and Spain have alternated in recent years taking for first place in the global olive production category and together can claim 25% total world production.
Within the European Union, the order of importance must be recalled as Greece, Portugal and France and outside they are Turkey, Israel, Algeria, Morocco, Tunisia, Egypt and Syria. Elsewhere there are the United States, Argentina and Australia plus some Asian islands.
Italian olive cultivations are obviously predominant in the south, especially in Puglia, and the Bari and Salento regions, in Calabria and Sicily. Not to be ignored are the olive areas in other regions, in Tuscany in Chianti and Mugello areas, Umbria, Marche in the Ascoli and Macerata areas with the mensa culitvar, Lazio and the rest of the south, from the Adriatic area, Abruzzo, Molise, Campania, Lucania and on to Sardinia and finally the Gardesano in Liguria. The real production in Italy is 0.5 million t/year for olive oil, 30% extra vergine, 20% vergine and the remainder for lamp oil.
In spite of remarkable production, Italy has a shortfall of some 100,000 t/year. The important humiliation of national production is that imported oil is marketed in Italy at prices decidedly lower than domestic olive oil and often with lower quality, especially as regards acidity which is returned to acceptable levels with unorthodox and often fraudulent methods.
