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 - September 07, 2013

From: Gainesville, TX
Region: Southwest
Topic: Pests, Trees
Title: Problems with Shumard Oaks and Crepe Myrtle in Cooke Co. TX
Answered by: Jimmy Mills

QUESTION:

I have a Shumard Oak Tree that has been in the ground approx. ten years. It has done great, even passing up some of my older Shumards. In August it began to lose its leaves at an alarming rate. They are very green when they fall. They fall single or in clusters. The end of the tree stem is still attached. None of my other Shumards(5)seem to be affected. I live in Gainesville (Cooke Co.) Tx.,just west of I-35. Also my Crepe Myrtle has been attacked by some kind of "Aphid", the leaves are shiny and sticky. Then they turn yellow with black spots and fall. The Shumard is in the back yard, the Crepe is in the front Yard. Could they be related?

ANSWER:

The problems that you describe are not related, and have different culprits involved.

The Crepe Myrtle, although it is widely planted all over Texas and the southern US, is a non native from southeast Asia. You are probably right to suspect aphids to be the cause of your problem. I am going to refer you to a previous question  from last August that explains aphids and honey dew, and contains several links that have even more information about aphids and their control.

For the Shumard Oaks Quercus shumardii (Shumard oak), three culprits come to mind. Two are types of longhorn beetles; twig girdlers and twig pruners. Since the fallen twigs have green leaves attached, twig pruners  are more likely causing the damage. Examine the fallen twigs, and if you see a concave end break, cut the twig open; you should find the fat white round-headed borer.

However, if the twigs have a slanted cut end or a sheared-looking end, then squirrels  are probably your culprits.  (more info)

The folks at the Cooke County Office of Texas Agrilife Extension can probably help you examine your twigs.

 

More Pests Questions

Growths on Shumard Red Oak leaves from Katy TX
April 01, 2013 - Our beautiful Shumard Red Oak has developed lots of light green grape like growths on the leaves. Please inform us what this could be and how we should treat it?
view the full question and answer

Desmodium spp. (beggar's lice) in Leander TX
November 11, 2011 - Our home backs up to a greenbelt on Blockhouse Creek in Williamson County, Texas (FM 1431 and Parmer Lane). The combination of the flood and drought has left our beautiful greenbelt with an abundance...
view the full question and answer

Texas Ash secreting sap in Lockhart, TX
July 05, 2012 - I have what I believe is a Texas Ash in my front yard that is secreting a sap with what looks like some wounds on it with some white stuff and with black and red looking ants as well as it has a lot o...
view the full question and answer

Danger of lichens damaging trees
September 26, 2007 - My mom lives east of Buda, Texas where she has planted many different kinds of trees, which are all over 10 years old. Now, they all have a moss or lichen growing on the bark of the trees. She is worr...
view the full question and answer

Purple sage with black residue on leaves in Georgetown TX
October 02, 2009 - I have 2 very healthy tx. purple sage that have developed a black residue on some leaves, and is a "sticky" substance..any ideas what this is and how to treat???
view the full question and answer

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