Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.
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.
From: Pflugerville, TX
Region: Southwest
Topic: Compost and Mulch, Grasses or Grass-like, Trees
Title: Removing grass under oak trees in Pflugerville TX
Answered by: Barbara Medford
Frankly, we're astonished that you HAVE grass under your canopy of oaks. We have dealt with the problem of things growing under oaks several times recently. See this previous answer, dated August 26, 2009, on why plants won't grow under oaks. Another, on ground cover under oaks, dated February 24, 2009. This excerpt from an answer dated Dec. 10, 2008 specifically addresses the failure of grass to grow beneath oaks:
"In general, plants need light (for photosynthesis), water (for photosynthesis and other processes), and minerals (which also help in photosynthesis). The grass growing under your pin oaks could be suffering from lack of sunshine, and it is certainly competing with the oaks for water and nutrients. The shade problem isn't easy to solve, but you can increase the amount of water and nutrients that the grass is receiving. Is the die back new, or has it been going on for some time? If it is new, you might try to determine what conditions have changed?"
Need we go on? You didn't say what kind of grass you have, probably it is non-native St. Augustine if it is surviving at all in all that shade. We don't like non-native grasses, obviously, but this may be a case of "if it ain't broke, don't fix it." If you want to have a go at it, the mulch would be okay, as long as you didn't get it up around the trunk of the tree, where it might encourage fungi and rot. It is an attractive ground cover under a tree, won't smother the roots and, as it decomposes, will in effect be composted to amend and enrich the soil. The newspapers could be another story, and from personal experience, the top layer of mulch tends to get kicked or blown around, and suddenly you are looking at the Sunday funnies and car advertisements all over your property. And they are blowing around too, which isn't going to endear you to your neighbors. If we were going to advise you on the best way to rid yourself of the grass, yes, pulling it out is the best way. And pulling it out, and pulling it out and pulling.... Grass can be very persistent and, again from personal experience, St. Augustine gets along just fine under mulch. It may be a little paler green from being covered by mulch, but IT'S ALIVE.
Rust spots on non-native red tip photinia
July 10, 2008 - I live in Oklahoma and my red tips have rust spots on leaves and some plants are losing leaves. This is a clay soil; can you give me any info. on how to solve this problem?
view the full question and answer
Bird nest fungus in Central Austin, TX.
August 21, 2012 - Hi,
I live in Central Austin and have different types of ground cover (such as silver pony foot)in my garden and have noticed huge patches of bird's nest fungi in between and under. Every time it ...
view the full question and answer
What to do with soil left over from new driveway in Austin
January 07, 2011 - When we had a new driveway put in in Mid-December, the topsoil and weedy grass was scraped into a low pile. I watered it and covered it with black plastic to kill all the plant matter. How long should...
view the full question and answer
Feeding live oak and redbud trees from Fredericksburg TX
October 23, 2012 - Can you please tell me what to feed my live oak and texas redbud trees that survived the drought? We have granite soil.
view the full question and answer
Dirt at tree base from Austin
November 03, 2012 - Hello,
I recently bought a home in Austin with a live oak tree which is about eight years old. The previous owner did exactly what all the experts say NOT to do, which was to mound dirt right up agai...
view the full question and answer
![]() |
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. |