Native Plants

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Tuesday - July 10, 2012

From: BOCA RATON, FL
Region: Southeast
Topic: Diseases and Disorders, Trees
Title: Sticky sap (honeydew) on car
Answered by: Jimmy Mills

QUESTION:

MY CAR IS CONSTANTLY COVERED WITH STICKY SAP. I LIVE IN AN AREA WITH MANY COCONUT PALMS AND OTHER TREES. COULD THE SAP BLOW AROUND EVEN THOUGH I KEEP CHANGING THE PARKING?

ANSWER:

It sounds as if you are experiencing the onslaught of honeydew. Honeydew is a waste-product of aphids and other sap-sucking insects such as scale. As honeydew is excreted by the sap-sucking insects, it becomes airborne and falls and coats any surface upon which it lands in the area.

This article from University of Minnesota Extension (use this link to get to the Sap Removal Article), another from the University of Kentucky College of Agriculture, and a third from the University of California Davis give a rather thorough explanation of honey dew and aphids, and their effects on plants. You may also notice blackening of the plants under the trees because of an infestation of sooty mold that grows on the honeydew.