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?


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

Tuesday - March 20, 2012

From: Austin, TX
Region: Southwest
Topic: Pests, Trees
Title: Leaf Galls on Live Oak
Answered by: Becky Ruppel


Hi - I have a live oak tree that always seems to have thinner foliage than our other two. Upon closer examination today I found small brown balls all over the mature leaves. The balls look and feel very much like peppercorns. What is this, and is this a danger to the tree? I did read the other post about Woody oak twig galls but based on that post I don't think that is what is going on here. Thank you for your time.


The tree in question sounds like it has leaf galls formed by the Mealy Oak Gall Wasp Disholcaspis cinerosa.  This wasp forms both stem and leaf galls depending on the stage in its life-cycle.  Galls are formed when an insect (in this case a type of tiny wasp) lays an egg just under the surface of a stem or leaf.  A gall is formed because the tree is stimulated by the presence of the egg, and eventually the hatched larvae, to grow a structure around the wounded area.  Galls are very common in oaks and are not considered harmeful to the health of trees.

For more detalied information about Mealy Oak Gall Wasp see the Mr. Smarty Plants post by Nan Hampton that talks about the specifics of the wasp, its reproduction, life-cycle, and affect on trees. 

The links in that post appear to no longer work. Below are updated links for the information cited in that answer about Mealy Oak Gall Wasps. 

"The Mealy Oak Gall on Ornimental Live Oaks in Texas"

"Gall Making Insects and Mites"


More Trees Questions

Will Mountain Laurels be harmed by juglones from my pecan tree?
May 06, 2009 - Hi. I just bought a house. It has a big pecan tree at the edge of the front lawn next to the street. I guess it's about 25 feet from the front of the house. I was thinking of planting mountain la...
view the full question and answer

Pecan with brown spots on the leaves
June 11, 2010 - Southern pecan, I am a 8 foot tall and 3 year old (young)tree. My leafs have brown spots on top and hard shell mound on the bottom, this is on about 3/4 of the of the leafs, could you tell me what th...
view the full question and answer

Erosion controlling plants for a shady Minnesota lakeside
August 11, 2015 - I live about 50 yards from a lake and there is a steep embankment. Recently someone decided to cut the trees off the embankment and now the dirt is eroding off the embankment as well as off my back ya...
view the full question and answer

Problem with baldcypress tree
May 27, 2011 - Two of my three 20 year old Bald Cypress trees appear to have leafed out but are now brown in parts of the tree. The brown area is at the tops of the trees which are probably 40 ft. high. They were...
view the full question and answer

Protecting a new patio from oak roots
September 01, 2008 - Hello, I have just formed up for a new patio. I have a Live Oak tree about 2' away from the patio. It has a trunk diameter of about 10", I believe 20-25 years old. Problem: I have 2 large roots in ...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center