En Español

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

Monday - August 23, 2010

From: Austin, TX
Region: Southwest
Topic: Diseases and Disorders
Title: What's that sticky stuff on plants under many trees?
Answered by: Jimmy Mills

QUESTION:

Here in Austin, I've recently noticed a sticky film appearing on shrubs, flowers, grass, etc. under many trees. It appears to be coming from the trees under which they are planted. The sticky film seems to be attracting white flies and other pests to these plants. Is there currently some sort of tree insect infestation that is causing this or are the trees stressed due to the recent heat? It doesn't appear to be moisture due to transpiration.

ANSWER:

What you are experiencing is the annual onslaught of honeydew here in Austin. Honeydew is a waste-product of aphids and other sap-sucking insects such as scale. As honeydew is excreted by sucking insects, it falls and coats any surface upon which it lands. Here is a previous answer from last Fall.

This article from University of Minnesota Extension , and another from the University of Kentucky College of Agriculture  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.

 


 
 

More Diseases and Disorders Questions

What is causing leaf drop on oak in Morgan Hill CA?
June 23, 2010 - Dear Mr Smarty Plants: We have a large, young Valley Oak (about 20 yrs) which is dropping leaves even now in early summer. I have a feeling that the problem might be an invasive weed that is flourishi...
view the full question and answer

Peeling bark on red oak in Plano, TX
April 08, 2010 - I have a red oak that was planted 2 years ago. The trunk is approx. 5 in around. The bark around the bottom of the trunk is peeling off. At first we thought it was rabbits so we put some rabbit gua...
view the full question and answer

Possible freeze damage to Texas Persimmon in Fair Oaks Ranch TX
June 27, 2010 - I have a Texas Persimmon tree that is in a green belt. It has leafed out and flowered for the eight years we have lived here. This year it leafed out then the leaves turned brown and dropped. The top ...
view the full question and answer

Should Mexican milkweed (Asclepias curassavica) not be used to attract Monarch butterflies?
November 20, 2015 - Should I remove Asclepias curassavica (Mexican milkweed) in my garden for threat of OE parasitic protozoan threat to Monarch butterflies? Is this threat as widespread as Chronicle implies? I had great...
view the full question and answer

Care for heritage roses
October 07, 2007 - Dear Mr. SmartyPlants, I took some cuttings from an antique rose my grandmother had.I had good luck , had some of them grow for me. Some of them have blooms and others are long and lanky stems but n...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center