En EspaŅol

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
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
Not Yet Rated

Thursday - October 23, 2008

From: Richmond, TX
Region: Southwest
Topic: Trees
Title: Knots growing on Arizona Ash in Richmond, TX
Answered by: Barbara Medford

QUESTION:

I have three Arizona Ash trees around my house the trunks are at least 15" in diameter. One of the three has at least 25 large knots growing on its trunk, some maybe 6-8" in size. What are they? Are they harmful to the tree? Thanks for your time and trouble.

ANSWER:

There are several things that can go wrong with Fraxinus velutina (velvet ash), including Texas root rot, nematodes, chlorosis, cankering, mildew, fungal infections and emerald ash borer. However, it sounds more like what your tree has is galls, which is ususually non-threatening to the tree, and involves a structure to protect larvae of some insect, most often wasps. When the galls show up, it's really too late to do anything about them, and they usually involve just one generation per year. See this article from the Kemper Center for Home Gardening Galls on Trees. It has suggestions for Integrated Pest Management, but just about all the information we could find on galls said it was nothing to really worry about. Most of the pictures we could find of galls were on oak trees, but they tend to be tree-specific, so something that likes to live on an ash may be causing the bumps on your tree. Look at these pictures of galls on trees to see if there are similarities to what your  trees are experiencing. 

Since we are not entomologists and, of course, cannot see your trees, we would suggest you contact the Texas A&M AgriLIFE Extension office for Fort Bend County.  This site has contact information and also an Horticulture link. They may recognize the symptoms and know what it is and whether you need to take any action about it. 

 

More Trees Questions

Can poisonous seed of wild plum be safely removed after steaming from Seymour IA
June 20, 2013 - I read on a related questions that you said the pit/seeds of all wild plums are poisonous. My question is this, can I juice the entire fruit for making jelly without removing the pit first? I have a s...
view the full question and answer

Identification of spiky red berry in Connecticut
September 25, 2011 - I found an odd berry outside of my school, none of the science teachers know what it is though. It kind of looks like a spiked cherry. It has spikes on the outside, a pit on the insde, and has pinkish...
view the full question and answer

Fast-growing, Horse-safe Pasture Tree for Okeechobee, FL
July 05, 2012 - I'm looking for a fast growing tree to plant in pasture that's safe for horses.
view the full question and answer

Problems with live oak in Carrollton TX
April 03, 2011 - This past winter was very hard on all the trees in our area in Texas, but added to our stress was the loss of three large Bradford pears just prior to the winter (23yrs old and over 50ft spans of limb...
view the full question and answer

Mexican Plum with wilted leaves in Austin, TX.
June 06, 2012 - I am new to Texas & have a yard with mature mexican plum trees. They are quite beautiful however as summer sets in I notice that the leaves appear "wilted". Is this normal or should I be providing...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2015 Lady Bird Johnson Wildflower Center