Expert: Jack DeAngelis - 10/25/2009

Question
Hi, I don't know if you can help, but I'd appreciate any feedback.
I've got an indoor garden with a decorative fig tree that's about 15-20 years old.
For awhile we've noticed that the stairs have been sticky, so we just cleaned them with soap and water. I recognized the stickiness is being caused by scale.
The tree is about 18 feet tall and hangs over all the other plants around it - causing our bird of paradise, a lily, and some other filler plants to get scale.
I need to get rid of this scale, but I'm concerned because of how long it's had scale that a simple washing won't be enough.
I'm also hoping that there's some way to get rid of it without damaging it or the walls around it.
Any help would be very appreciated.

Answer
Katie,

As you know scale insects can be very difficult to control. Infestations develop slowly so they tend occur on older plantings. Adult scales are covered by a waxy shell which makes treating them with something "soft" like insecticidal soap almost impossible (soap works well on the crawler stage however). You could hand-clean all surfaces with alcohol or insecticidal soap and physically remove the insects but this will take time and repeated treatments. There are no systemic insecticides available for in-home use. If this is a commercial setting (interior plantscape), however, you could use one of the systemics that contains imidacloprid. Here's an article about imidacloprid http://www.livingwithbugs.com/merit_insecticide.html that may be useful. Be sure to check the product label carefully.

Jack DeAngelis
http://www.livingwithbugs.com