Citrus Scab (Elsinoë fawcettii), is a fungal disease that affects Citrus trees. It strikes during humid and wet weather conditions.
Plant Parts: Fruit, leaves and twigs
Season: Spring - Autumn
Symptoms: Leaf Symptoms: Lesions on leaves, especially Temple with a tan-to-gray pustule at the tip.
Fruit Symptoms: Symptoms tart with slightly raised pink-brown lesions which develop into warty or corky protuberances that can crack. The colour changes to yellowish brown to dark gray.
Control: If you have caught citrus scab early then applying a copper spray at petal fall (always read the directions of anything you apply on your fruit tree), this will help with control. The copper spray protects the developing fruit. If your fruit tree is heavily infected on foliage, follow up with another spray of copper in late summer.
Preventative: Clean up trees by pruning out heavily infected sections of tree. Do not wet the canopy of the tree when watering. Good balancing and removal of dead twigs on your fruit salad tree will help keep this fungal disease at bay as will an annual spray of copper in Spring and Autumn.
References: References: NSW Department of Primary Industries, QLD Department of Agriculture & Fisheries, Id Tools, University of florida, Citrus Foliar Fungal Diseases, Photo Credits: M.M. Dewdney, L.W. Timmer, J.D. Burrow, and our FST team.
