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
1 rating

Tuesday - September 04, 2007

From: Kyle, TX
Region: Southwest
Topic: Trees
Title: Possibility of oak wilt or iron deficiency
Answered by: Joe Marcus

QUESTION:

This spring my two oak trees, 4" and 7" in diameter, in my yard in Kyle started showing very light green leaves with green veins. I've been told this is chlorosis, so I treated them with a couple of granular products containing iron, purchased locally. Also, I started watering them weekly. This treatment seems to be successful. The appearance of light green leaves has decreased, and growth on both trees has greatly increased in terms of new leaves and branches. My question: The new growth shows the light green leaf color, and on one of the trees the new leaves seem to start out with a brownish color. These new leaves then change color from light brown to to light green, and finally change in color to be pretty much like the mature leaves. Should I regard the color of the new leaves as indicating chlorosis, or are new leaves supposed to start out light green or brownish color? Should I continue the iron treatments, and if so how often? Another question: The 4" diameter tree has black dots on the leaves. I've been told this is a fungus and not to worry about it. Should I treat this tree for fungus? Thanks for your help. or

ANSWER:

We don't want to unduly alarm you, but you should consider the possibility that your trees may be infected with Oak Wilt Disease. Some of the symptoms you describe could indicate Oak Wilt Disease. The Texas Oak Wilt Information Partnership website provides a tremendous amount of information about diagnosing and treating trees infected with the Oak Wilt fungus as well as preventing its occurence and spread.

However, since adding iron seemed to help your trees, chances are they are suffering from iron deficiency. New oak growth is often a bronze color which changes to green as the new stem and leaves mature. This is a normal condition and is, in fact, often very attractive.

The black dots on the leaves of your tree may or may not be a fungus. To find out for sure, it is a good idea to contact the state Cooperative Extension Service agent in your county for a diagnosis.

 

More Trees Questions

Planting and care of Desert Willow in Golden Valley, AZ.
May 17, 2013 - I got a desert willow to plant in yard. Some of the leaves dried out before I could plant. Will that stop the tree from growing into a decent size tree or stay as a shrub?
view the full question and answer

Cause of chlorosis on dogwood
July 23, 2007 - Help!! I have been gone for three days, when I came home and looked out my back door I discovered that one of my huge dogwoods was turning yellow. We have had more than our share of rain this year and...
view the full question and answer

January good time to plant live oak in January from Manor TX
January 19, 2014 - I want to plant a Live Oak in January. Is this a good time to plant it?
view the full question and answer

Poolside tree for Whitehouse TX
May 29, 2012 - What would you recommend for native shade tree or flowering tree on the north side of a swimming pool in East Texas/Smith County? Trying to avoid too much dropping of flowers, nuts, etc. Looking to ...
view the full question and answer

Species of hackberry best for wildlife from Georgetown, TX
February 21, 2014 - Which species of Hackberry tree is the best for wildlife in Georgetown, TX (just north of Austin)? Your Plant Database says Celtis occidentals is "among the BEST food and shelter plants for wildlife,...
view the full question and answer

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