How to fight the olive fly naturally? Soil work and clays.

85,707 views

Published on May 24, 2018

About :

Jean Yves Meignen, a plant craftsman and gardener at the Valsaintes Abbey, explains how to fight the olive fly naturally. This fly appears in June, after the flowers have fallen from the trees, and it lays an egg in the fruit from which a worm will be born that feeds on the olive. The olive will then fall to the ground and be lost. DEVELOPMENT CYCLE: The adult can live up to 9 months. It can travel about ten kilometers per day. The lack of water is very penalizing for adults. This explains why the survival rate of adults is very low when they find themselves in conditions of severe drought. FLIES IN WINTER AND SPRING The vast majority of olive fly populations spend the winter in the pupal stage, under the canopy of trees in the first few centimeters of soil. The pupa is very resistant to climatic conditions. However, below 0°C, the survival of pupae is very reduced, natural mortality in winter is very high: less than 20% of pupae will survive the winter. A first technique therefore consists of working the soil at the beginning of winter a few centimeters deep under the olive tree in order to bring these pupae to the surface. The latter will then be cold and/or can be eaten by birds or by a hen. FLIES IN SUMMER During the summer, as soon as the olives reach 8 to 10 mm in length, the first eggs are laid in the olive. Females can lay 400 to 500 eggs in a few days. Females lay one egg per olive and the maggot develops inside the pulp of the olive by digging a gallery. A generation of flies then develops in about a month. Depending on the climatic conditions, three to five generations follow one another from June to October. At the end of its development, the larva eats the pulp just under the epidermis and prepares its exit hole then moves back into the fruit to pupate. Pupation takes place in the form of a pupa for about 10 days in summer. Once out of the pupa, the new adult dries its wings for a couple of hours then flies away. It is ready to reproduce after a few days. In autumn, when temperatures drop and the flesh becomes milky, the larva drops to the ground. Pupation takes place in this case on the ground and spreads out until the end of the cold period and the cycle begins again. To limit the development of the olive fly, you can spray white clay or Kaolinite on young fruits. (formation of fruits and start of the first flights of flies in June or July depending on your region). The clay must be diluted in water at a rate of 30g / liter of water. Or a tablespoon of Kaolinite for a liter of water to protect a normal-sized olive tree. The clay, once deposited on the young olive in formation, prevents the fly from locating the fruit and therefore laying its eggs there. In Provence, this technique is very effective because the summers are dry and we do not have to repeat the operation after each heavy rain. For more advice, go to your nursery, horticulturist or your local garden center. Tips are also available on www.jardiner-autrement.fr

vidoe Comments

Trend Videos