Sexual confusion.

-"What are all those people doing in the vines with their basket in the hand ? It's not harvest time !"

That is the question that you might ask if you had crossed today the vineyard of Villers-Marmery (1er Cru Montagne de Reims). Well, this tuesday the 16th of April 2013 is the day when all the growers of the village decided to fight gainst two butterflies, we should say their caterpillars : "The Eudemis and the Cochylis".

Eudemis and Cochylis are part of the most damaging pests for the clusters. They perforate the berries, causing injuries that offer the best conditions for moistures and grey rot.

This method of struggle consist in attaching in the vines the small capsules (we called them rak) at the rate of about 500 per hectare. The will spray syntethic pheromones equivalent to the one of the female of both butterflies species. This high concentration will not allow the male to identify femalesn and therefore their will not reproduce in the vines...and so, they will never lay in caterpilars in the vines.

These pheromones are specific to these two species. There is no interaction on the rest of the insects. And because the spray in highly concentrated (only above the vineyards) the effect is on a small area, and butterfly can reproduce while they fly over the forest or the fields.