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
1 rating

Friday - October 19, 2012

From: Houston, TX
Region: Southwest
Topic: Pests, Trees
Title: Are fuzzy oak leaf galls harmful to post oak trees?
Answered by: Nan Hampton

QUESTION:

Are the fuzzy balls on the undersides of our post oak trees harmful?

ANSWER:

The fuzzy balls are galls formed by the tree leaf in response to the feeding of the larvae hatched from an egg deposited by a tiny gall wasp in the Family Cynipidae, Genus Andricus.  Here are photos of Andricus quercusflocci galls that form on leaves of Quercus alba (white oak) and Quercus prinus (chestnut oak).  Andricus pattoni is reported to be the species that lays eggs on postoaks, but I could find no photos for that species of gall wasp.  Here is a link to an article about other Oak Cynipid Galls from the Department of Entomology, University of Minnesota.  You can see other types of galls in this article from the University of Wisconsin-Milwaukee and here is more information and photos from the University of PennsylvaniaHere is a link to an article on Randy Lemmon's Gardenline on KTRH radio about galls on oak trees in Houston in 2010.

In general, the galls are not harmful to the trees and there is really no insecticide that is effective since the wasps are tiny and not easily seen, plus the larvae are well-protected from pesticides within the galls.  Additionally, insecticides applied are very likely to be harmful to beneficial insects.

 

More Trees Questions

Identification of tree with red feathery leaves
March 08, 2012 - What is the name of a tree with dark red leaves, feathery, slim trunk; maybe in the pepper family? Jedi?
view the full question and answer

Selection of a small variety of Desert Willow for SE Texas
August 02, 2011 - Looking to plant desert willow as shrub. Any helpful tips to keep height down and plant full or bushy.
view the full question and answer

Which is best-Oklahoma Redbud or Texas Redbud in Austin?
March 25, 2010 - I live in Northwest Austin and would like to plant a small redbud tree in my front yard. My yard gets full sun. Which is better - the Texas redbud or the Oklahoma redbud?
view the full question and answer

Plants for full-sun landscape
November 20, 2007 - I live in a very rocky area just outside of Fort Worth, TX. It's taken me all spring, summer & now I'm going into the fall, to landscape just 30 feet in front of my house. The front of the house get...
view the full question and answer

Wanting to grow a Buckley Oak in Amarillo, TX
January 20, 2016 - I live in Amarillo Texas in the Texas Panhandle. I recently became interested in the Buckley Oak and was wondering if it might grow well here and if so, where I might find one that I could purchase a...
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