Rent Shop Volunteer Join

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

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
Not Yet Rated

Saturday - April 30, 2011

From: Austin, TX
Region: Southwest
Topic: Pests, Shrubs, Trees
Title: Holes in leaves of wax myrtle from Austin
Answered by: Barbara Medford

QUESTION:

I just purchased 4 of the 5 gallon Wax Myrtles at the last spring plant sale and after planting them, they are getting eaten by bugs leaving holes in the leaves. I can't find any of the bugs doing the damage. What would be good to spray on these wax myrtles for insect control? Thanks!

ANSWER:

Water. And if that doesn't work, add a little pure liquid soap to the water, and spray again.

Okay, now we've had our fun, we'll get serious. We are neither entomologists nor plant pathologists, but our experience as gardeners tells us this is probably aphid damage. Look on the underside of the wax myrtle's leaves-do you see tiny white specks moving around? Are there ants present? Is there a whitish deposit on those undersides, some of which may be developing a black moldy appearance?

Sooty mold is a fungus, or more commonly a complex of two or more fungal species, that grows on honeydew or on plant exudates. Honeydew is a waste-product of aphids and other plant-sucking insects. As honeydew is excreted by sucking insects, it falls and coats any surface upon which it lands. Sooty mold fungi invade and live upon this sugary coating. These fungi do not infest the leaf ifself. Thus, sooty mold may often be found growing on any exposed surface beneath aphid-infested trees and shrubs. Sooty mold can cause great harm to plants, however, by blocking sunlight to the leaf surface below and diminishing photosynthesis.

Sooty mold can often be successfully removed by rinsing with water from a garden hose. However, this will be most effective after the aphids or other honeydew-producing insects are destroyed. Sometimes sooty mold development is so severe and persistent that only time and exchange of leaves through the growing seasons will remove it all.

Aphids are not especially difficult to control and non-chemical methods are usually very effective. Insecticidal soaps are often the remedy of choice for many gardeners. Various brands of insecticidal soaps may be found at just about any retail nursery or garden center. Be sure to read and carefully follow all label directions when using any pesticide, organic or chemical.

 

 

More Trees Questions

Is post oak resistant to oak wilt from Dallas TX
November 22, 2013 - I am confused. The NPIN website says that Post Oak IS susceptible to oak wilt, but all the other information I have been able to find says that it is resistant to oak wilt and rarely gets the diesase....
view the full question and answer

Live Oaks and Foundations
September 22, 2009 - I have a young live oak (18 inch trunk at it's base) growing within four feet of my house. What kind of damage can it cause my foundation? Need your help!
view the full question and answer

What kind of native Junipers will grow in zone 7?
June 25, 2009 - What kinds of native Juniper will grow in zone 7 ? (besides Juniperus scopulorum and J.virginiana).
view the full question and answer

Overwatering Texas Mountain Laurel from Rosanky TX
June 06, 2012 - I just read your article in the Statesman about over watering Mt.Laurel. Now I know why my lovely 15 year old tree is dying. We put in new grass this winter and I watered too much. Is there any hop...
view the full question and answer

Live Oak Suckers Reprise, Austin TX
July 06, 2014 - Referring to an entry dated March 11, 2011 about Live Oak suckers - what happened to the suckers covered with newspaper and cardboard?
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.