What is this on my mother-in-law’s satsuma tree? It is on most of the tree's fruit.
Thanks, Karl H.
This is an insect infestation of wooly whitefly. Several applications of a light horticultural oil, such as the Year Round Spray Oil or All Seasons Oil should be effective for the wooly whiteflies on the satsuma tree. You must spray on top and under the leaves and coat the fruit thoroughly. Oils kill by coating and suffocating the insects. Make two applications following label directions.
Consumer Horticulture Specialist
The LSU AgCenter and the LSU College of Agriculture