What determines the number of feet an olive tree has?
By “olive tree feet” we may mean the number of trees planted in an area comprising one hectare, which may range from 20 olives per hectare in certain parts of Tunisia, to over 2,000 in some superintensive plantations. This variability mainly depends on the climate of the area, the availability of water –whether from rain or watering systems-, the level of mechanization and, above all, the harvesting system used.
On the other hand, “olive tree feet” may also mean the number of trunks that shape each tree. In this sense, each of these feet generally has just one sole stake, although at times these can be mixed up with olive trees which, with just one trunk, have suffered drastic
reconversion pruning –for instance, after a catastrophe, a fire or a very intense frost- and have been reborn with various shoots emerging from the same base.
In any case, the reasons that drive the olive farmer to cultivate one or more feet are complex, although, one curious explanation is the fact that in hot areas the existence of various feet aims to create a microclimate within each cluster of olive trees with a view to increasing their activity even at high temperatures.
Nonetheless, this type of olive groves with various feet need long periods of time to reach their maximum yield and, moreover they are difficult to mechanize. This is why this type of plantation has been replaced with others which, while they still have the same number of feet there is a distance of at least seven metres between each tree, or even by the super-intensive groves in which the olive trees are planted one metre away from each other in rows separated by 4 or 5 metres.
Alberto Alecha, olive grove technician for the Mesa del Aceite y del Olivo de Rioja Alavesa