Host an Event Volunteer Join Tickets

Your gift keeps resources like this database thriving!

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
8 ratings

Thursday - July 14, 2011

From: Salado, TX
Region: Southwest
Topic: Diseases and Disorders, Trees
Title: Care of a live oak with decay and perhaps fungus on trunk
Answered by: Guy Thompson

QUESTION:

I have a huge live oak on my property in Salado that just lost a very large branch. The branch had decay in the center and also has a variety of bugs in it, espeically since it has been on the ground for a few days now. what can I do for this tree to help it survive. I'm not sure how much rot is in this tree, but can see a darkend vein down one side ? Also, there is a type of white substance on the bark on one side that is hardened and on the ends of bark outcrops or projections. I've never seen anything like it. Otherwise, the tree looks perfectly healthy all leaves green even on the branch that broke off.

ANSWER:

Decay in the center of a branch or the center of the tree's trunk involves the heartwood, which is already dead.  The important part of the trunk is the cambium, which is the layer a few inches thick (depending on the tree's size) under the bark.  That is the living part of the trunk.  If your tree's trunk has a cavity filled with soft decayed wood, carefully remove it, making sure not to damage the more solid wood.  Until recently it was recommended to fill the cavity with some impervious material like concrete to provide strength to the trunk.  That is now thought to be harmful, and experts suggest leaving the cavity unfilled.  The darkened vein down one side of your oak should not be treated with wound paint or other material.  The white substance on the side of the trunk may be a fungus.  This web site will give you information on fungi infesting oak trees.  If it appears that your tree does have a fungal infection, Mr. Smarty Plants would recommend that you contact your local county extension agent for help in treatment.  Large oaks like yours are too precious to risk losing.

 

More Diseases and Disorders Questions

Failure to thrive of Esperanza in Houston
July 07, 2009 - Esperanza plant. I have 3 of these plant in my flower bed for the last 10 years. They get west sun. Over the last three years they have bloomed initially but then the new growth is deformed. The best...
view the full question and answer

Problems with mature cottonwood in Justin TX
September 17, 2012 - I have a very large, 90" circumference, approx 60' tall, cottonwood tree in my front yard that appears to be sick. The trunk splits at about the 4' level into 2 parts. at that split is a 10" wide...
view the full question and answer

Need help controling suckers from an ornamental plum in San Pedro, CA.
August 10, 2010 - I have an ornamental plum tree in my garden which produces a lot of suckers in my vegetable beds. I do not want to use harmful chemicals and cutting them back is a hopeless venture and leaves small...
view the full question and answer

Powdery Mildew on Monterrey Oak
July 30, 2015 - Monterrey oak developing gray-white patches on some but not all leaves leading to wilting. could this be powdery mildew? Tree not stressed. Thanks. Best treatment?
view the full question and answer

Death of mature Eve's necklace in Fredericksburg, TX
July 12, 2010 - A friend mentioned his mature Eve's necklace had died this year. The next day I walked past my own mature Eve's necklace(about 5 years old)and it was dead! What could have happened? Thanks.
view the full question and answer

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