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
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

Lantanas failing to bloom, turning brown
October 06, 2007 - The lantana in my front yard does not bloom, is not overwatered but does get watered, leaves turned brown and plants generally have not grown. The lantana in the rest of the yard are in bloom and lo...
view the full question and answer

Yellowing leaves on young bur oak
August 06, 2007 - I saw your response on 7/25 about leaves on mature live oaks turning yellow, then brown because of excessive rain. The same thing is happening to our young burr oak. Leaves are turning yellowish, th...
view the full question and answer

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

Possible reasons for death of Wax Myrtle (Morella cerifera) in Austin
April 04, 2006 - Several wax myrtles in my neighborhood appear to have died. Should we have the soil or tree checked for fungus, or should we atrribute the death to freeze or age of the trees?
view the full question and answer

Should I use wound paint when pruning my live oak tree?
February 04, 2010 - When trimming live oak branches, is it best to coat the wound on the tree? I have been doing this but have recently heard that it can actually be bad for the tree.
view the full question and answer

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