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
Not Yet Rated

Friday - November 22, 2013

From: Dallas, TX
Region: Southwest
Topic: Diseases and Disorders, Trees
Title: Is post oak resistant to oak wilt from Dallas TX
Answered by: Barbara Medford

QUESTION:

I am confused. The NPIN website says that Post Oak IS susceptible to oak wilt, but all the other information I have been able to find says that it is resistant to oak wilt and rarely gets the diesase. Can you tell me where the information on the NPIN website originates from or if perhaps it is an error?

ANSWER:

Don't feel alone. The facts on Oak Wilt are confusing to everyone. We did find the line on our wepage for Quercus stellata (Post oak) that you mentioned:

"Susceptible to oak wilt. Not often used in landscape situations. Slow-growing and long-lived." The Post Oak is a White Oak.

We will go to another source, texasoakwilt.org, for some clarification, if possible. We suggest you scan the whole site. From the Introduction to that site: "All oaks (Quercus spp.) are susceptible to oak wilt to some degree, but some species are affected more than others." Also from that website:

"Patterns of Tree Mortality

 Most live oaks defoliate and die over a 1- to 6-month period following initial appearance of symptoms. Some live oaks take longer to die, and a few untreated trees may survive many years in various stages of decline. Occasionally, a few live oaks in an oak wilt center may escape infection and remain unaffected by the disease.

Red oaks never survive oak wilt and often die within 3 to 4 weeks following the initial appearance of symptoms. During summer months, diseased red oaks often can be spotted from a distance because of their bright autumn-like coloration in contrast to the surrounding greenery."

From the Texas A&M Forest Service, here is a map of the counties in which oak wilt appears in Texas. Also from that site:

"Oak wilt has been found in over 73 counties and in almost every city in Central Texas, as well as, Abilene, Midland, Lubbock, Dallas, Ft. Worth, College Station, Houston, and San Antonio. It can be a problem wherever live oaks tend to be the predominate tree. It does not matter whether they are transplanted or naturally grown. An individual tree’s age, size or previous health status does not make it more

"Red oaks, particularly Spanish oak (Quercus buckleyi), are very susceptible to the fungus.  White oaks, like post oak (Q. stellata) and bur oak (Q. macrocarpa), are resistant to the fungus and rarely die from the disease."

Bottom line: If you want to add oaks to your landscape, a post oak is probably less  likely than the red oaks and live oaks to contract Oak Wilt. If you choose the post oak or have some on your property that you wish to protect, you should still follow the management policies from the Management section of texasoakwilt.org.

 

From the Image Gallery


Coastal live oak
Quercus virginiana

Coastal live oak
Quercus virginiana

Texas red oak
Quercus buckleyi

Texas red oak
Quercus buckleyi

Post oak
Quercus stellata

Post oak
Quercus stellata

More Trees Questions

Transplanting a redbud in Boerne TX
August 29, 2012 - Hi there, My question is when is it safe to transplant a native tree? I have a redbud tree come up in m flower bed I want to try to transplant it instead of cutting it out. It is very young - maybe 4-...
view the full question and answer

Thorn bushes for a fence in Puerto Rico
November 17, 2015 - I'm looking for thorn bushes that grow in Puerto Rico. Want to use as fence to keep wild life in. Thanks, at least 5 ft tall so dogs can't get out.
view the full question and answer

Plant ID in Flower Mound TX
June 23, 2009 - I have a large native tree in the back yard, leaves resembles a live oak, but evergreen,& small white flowers in the spring, very tall vase shaped tree. It had no acorns or berries.
view the full question and answer

Small trees for Alberta
March 17, 2011 - I would like to know if there is a short, 15 feet and under, deciduous tree that can be grown outside in Calgary, AB
view the full question and answer

Plants for shade under pine trees in Grapevine TX
May 16, 2010 - What plants are good to put under pine trees in the shade? I live in the Dallas Fort Worth area? The previous owners stuck a Japanese Maple in there that seems to be ok and some sort of holly bush (n...
view the full question and answer

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