Question
I have been fighting for the last year with little white and brown bumps on my plants that leave sticky stuff on the leaves.  I did some research and found out it was scale.  I have tried the scale plant spray, rubbing alcohol and even trimmed my plants down to nothing but they just seem to jump to another plant.  How can I get rid of these things and save my plants. The worst one our my ficus trees I even cut them all the way down to basicly nothing and still can't get control of these pests.

Thank you,
Tracy  

Answer
Hi Tracy,

I understand your frustration with controlling scale insects. They can be difficult to eradicate.

The key is thorough and complete coverage of whatever spray you are using. A rubbing alcohol and soap solution can be quite effective, but only if you drench all leaf and stem surfaces so they are dripping wet. The Q-tip application approach doesn't work. The reason is that the immature scale insects are virtually invisible and usually missed unless you get complete coverage with the spray.

Horticultural oil is another good treatment option. If you are able to spend a little money, I have found that a product called Brand X Foliage Cleaner is very effective at killing scale insects, as well as cleaning plants. It is available through Southwest Plantscape Products in California (www.southwestplantscape.com). Their phone is 1-800-333-7977. It is a silicon-based product so it is very slippery. Its ability to penetrate is probably the key to its effectiveness because it gets into the tiny crevices that other sprays miss.

If you want to try a pesticide, Imidacloprid (trade names: Merit and Marathon) works very well on scale either as a soil drench or as a foliage spray. Follow label directions very carefully.

Trimming large plants, such as Ficus trees, makes the spraying treatment a lot easier because there is less to spray.

All plants that you suspect as having scale should be treated pretty much at the same time to prevent re-infestation. You may want to set aside some time when you can gather together your treatment supplies and treat all of the supect plants at once. If the weather is cooperative, doing this outside where you don't have to worry about spray run-off can make the task easier.

Good luck and please let me know if any of this is unclear or if you have any additional questions.

Regards,
Will Creed, Interior Landscaper
Horticultural Help, NYC

You can E-mail me directly at: [email protected]

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