En EspaŅol

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
    
 
See a list of all Smarty Plants questions
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
1 rating

Thursday - January 27, 2011

From: Melbourne, Australia
Region: Other
Topic: Cacti and Succulents
Title: Scale on Agave attenuata from Melbourne, Australia
Answered by: Barbara Medford

QUESTION:

I have an agave attenuata in a pot. It has been attacked by scales. I have been spraying it every 3-4 days at night with a chemical sold to me by the local gardening store. It's not helping and I am worried that the scales will take over the entire plant and kill it. At the moment, the only unaffected parts are in the middle and not yet opened out into leaves. I am wondering if the next step is to cut off the affected leaves? I have read your page on pruning agaves so I am prepared if that is the next step.

ANSWER:

We were just going to mention that Agave attenuata is native to Mexico, not to North America, which is our ordinary range of expertise, when we noticed you were writing us from Melbourne, Australia. It's not native there, either. We don't know what your climactic conditions are, or your normal temperatures, but we will try to find some literature that will perhaps help.

Begin by reading this article from the University of Arizona Cooperative Extension on Problems and Pests of Agave, Aloe, Cactus and Yucca. You will have to scroll down to Page 6 "Fungal diseases of leaves and pads," and then to Pages 9 and 10, "Coccineal scale, coccide scale, soft scale."

Next, take a look at this University of California Integrated Pest Management website on managing pests of the agave family (agaves and yuccas). Clicking on "Armored scales" on the right-hand side of that page will take you to a page to help you identify and then manage the scale you are experiencing. This article emphasizes that you need to know which scale you are dealing with in order to choose the proper control. Possible controls are discussed, and you should then be able to obtain a specific spray or oil for the appropriate treatment.

The article on diseases and pests of agaves is quite extensive, but you should read it all as it advises against the spraying of certain controls. It does not, however, recommend pruning. You would probably want to hold off on pruning and try to get the scales to go away, or at least become more manageable, then prune only heavily damaged leaves.

 

More Cacti and Succulents Questions

Removal of mature agaves
November 20, 2007 - Hello- we live in Austin, TX and have a bed of different varieties of agave. They are near the walkway to our house, and are so out of control they pose a hazard to our guests walking up to the house...
view the full question and answer

Plants for 16th floor of condo in Panama City Beach, FL
May 30, 2012 - My husband and I have a COSI on the west end of Panama City Beach, Fl. I love plants and flowers and live out of state. Our condo is on the 16th floor and directly on the gulf. What type of plants ...
view the full question and answer

Problems on Prickly Pear Cactus in Illinois
November 19, 2014 - I have a fungus on my prickly pear cactus that is not a bug. I tested it and my fingers didn't turn red when I squeezed them. So how do I get rid of this as it is spreading to my other cacti?
view the full question and answer

Dealing with beetles feeding on cholla cactus
June 20, 2010 - Hi Mr. Smarty Pants, I bought a Cylindropuntia imbricata from the Wildflower center and it was growing like crazy. I recently noticed a lot of beetles feeding on it. Some are black and some are gra...
view the full question and answer

When should cochineal bugs be on prickly pear cactus?
January 05, 2012 - I am a fibers artist that would like to harvest the cochineal bugs from the prickly pear cactus. I would like to know what time of year should I expect to find the cochineal bugs around the Austin ar...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP | STAFF
© 2015 Lady Bird Johnson Wildflower Center