🦠 Esca

Esca is a disease of grapevine wood. Fungi settle inside the trunk and thick branches and gradually rot the wood. The disease develops slowly, but its symptoms can appear suddenly.

Esca has two forms. The chronic form produces tiger-stripe patterns on leaves: the edges turn yellow or red while the middle stays green. The acute form, called apoplexy, can kill a vine in a few days or even in a day: in summer the vine suddenly withers.

The fungi enter through the wounds left by pruning. That is why the disease is more common in old vines, which have accumulated many cuts. There is no effective cure, so growers try to prevent infection: they prune in dry weather, treat wounds and remove diseased parts.

Esca occurs in many wine countries and is regarded as one of the serious vine diseases. It forces the replacement of old vineyards and causes losses. This is one reason old vines are especially prized.