Wind Dynamics in Citrus Orchards and Fruit Damage

Abstract

In Uruguay, citrus orchards are protected by live fences, constituted by tall trees. While it manages to reduce the average wind speed, it does not reduce the amount of fruit discarded due to wind damage. The rubbing of the leaves’ edges against the fruits would be the most significant source of damage in young fruits. A field test in a box of citrus plantations was performed, in which artificial fences were installed for wind protection. In the fence protected zones, an increase of the exportable quality fruit was detected. As a difference to live fences, artificial fences are designed to control the turbulence of tree leaves’ size or smaller. Citrus tree’s response under wind action was studied in a wind tunnel for flows with mean velocities between 1 m/s and 6 m/s, and with different energy content at small-scale turbulence. At a fixed mean velocity, if the energy at small-scale turbulence was high, the leaves moved with an amplitude significantly greater than when this energy is low. This leads us to infer that the leaf would remain significantly more time away from the fruit when the energy at the small-scales is greater than when the energy is low, reducing the leaves’ mechanical action and thereby the resulting damage.