Cotton wool (also known as cotton wool or olive fleas), Euphyllura olivine, is an insect that infects olives and is very common in Mediterranean countries, especially in Italy and Greece. The common name of the insect is due to the characteristic white waxy secretions that cover the body of the larvae and the affected organs. These secretions come from glands located in the back of the abdomen. It is widespread in all the olive growing areas of the Mediterranean and has the exclusive host of the olive tree.
Damage it causes
1. It forms colonies in the inflorescences, which are covered with cotton secretions, thus preventing fertilization.
2. In addition, it weakens the trees due to suction of vegetable juices, which can negatively affect production. The feeding of the nymphs by breaking down the cells and sucking them, they destroy the olive tree. The reduction in production can exceed 40% of the total production in some areas.
3. In general, the second generation is the most dangerous, due to its immediate nutrition which, in addition to its influence on production, also has an indirect effect, ie the production of waxy secretions that cause the abortion of flowers.
4. Finally, it promotes the growth of tobacco fungi.
Insect life cycle
Its life cycle is limited to 3 months and the female is very productive at the ideal temperature of 20-25 ° C, reaching the point of laying more than 1.000 eggs. The females begin the deposition from March to April with the beginning of the vegetation of the olive tree. The eggs are laid on the tops of the small branches or between the young leaves. Hatching occurs after an incubation period of 8-12 days. The second generation grows in inflorescences and remains dormant in summer, when the temperature exceeds 27 ° C. When the weather gets better and especially during September, the adult insects reactivate. Then the 3rd generation appears. The evolution of the nymphs lasts from 24 to 35 days. It overwinters as it blooms in the axils of shoots and leaf stems and in the spring it lays its eggs on the buds or inflorescences.
Tackle
The fight against cotton is done biologically and chemically.
When there are significant infestations of cotton, we recommend spraying the olive trees with summer pulp. The summer pulp is based on paraffin oil and is one of the ecological plant protection products for the olive. It is good to spray with summer pulp on irrigated olive trees at dusk, always with temperatures below 28 ° C. The chemical treatment of the insect is done by spraying with commercially available insecticides. Also, it has been observed that in dry periods the eggs and nymphs are destroyed.
