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 - June 13, 2013

From: Austin, TX
Region: Southwest
Topic: Non-Natives, Diseases and Disorders, Grasses or Grass-like, Trees
Title: Brown rings on grass under live oaks in Austin
Answered by: Barbara Medford

QUESTION:

There are brown rings in the grass at the dripline on several Live Oak trees in our neighborhood. What causes this? The trees appear healthy.

ANSWER:

You did not say what grass you or your  neighbors have. The rings might be a problem in the grass rather than originating from the tree. We will investigate brown rings in non-native grasses bermudagrass, St. Augustine and zoysia.

Although no grasses do well under trees, oak trees have more of an influence on the grasses. Oak, walnut, pecan and other trees exhibit allelopathy which means they exude substances harmful to competitive plants beneath them. Here is a a previous Mr. Smarty Plants answer on how we feel about lawns under trees. Between the shade, the allelopathy and the competition of extensive root systems for water and nutrients, grass growing under trees is always difficult. Since all three of the grasses we mentioned above are non-native to North America we don't know much about them, but will try to find some research to help you make a diagnosis.

Bermuda Grass: From WalterReeves.com Bermudagrass diseases - brown patch.

Zoysiagrass: From Missouri University - Issues of Zoysiagrass Lawns

St. Augustine Grass: From Cypress Isle (FL) Master Gardeners- St. Augustine Grass, Common Summer Problems.

Of course, if you are growing Bouteloua dactyloides (Buffalograss) or Habiturf they both need at least 5 hours a days of sun and won't be growing under the trees anyway.

 

More Grasses or Grass-like Questions

Raised beds over lateral lines in Solgohachia AR
January 02, 2010 - I would like to build raised flower beds over my lateral lines. They would be planted with strawberries and perennials. Will this cause any problems with the absorption into the ground or not lettin...
view the full question and answer

Mixture of native grasses as opposed to buffalo grass monoculture
November 26, 2003 - My husband and I just built our home on Lake Travis. Our lot is very rocky and is on the side of a hill. We would like to plant something on the incline at the front of our home that doesn't need a l...
view the full question and answer

Failure to thrive of Cherokee sedge in Spicewood, TX
May 18, 2009 - I have several Cherokee sedges, just planted in March. Three of them are doing fine, but the rest look like they're dying. Some are right next to one that is doing great. Any ideas?
view the full question and answer

Setaria scheelei grass for San Antonio
March 21, 2011 - It seems that ornamental grasses for dry shady places are few and far between. Southwestern Bristlegrass (Setaria scheelei) is exactly what I'm looking for and would solve all my problems! Only I c...
view the full question and answer

Plants for creek bank in North Carolina
April 29, 2011 - I would like a list of plant options to plant on an almost vertical creek bank in some location in Charlotte, NC. The creek runs through a 300 acre basin, maybe 3 or 4' high banks and I have never se...
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
© 2014 Lady Bird Johnson Wildflower Center