Native Plants
![](../_images/smarty_plants.gif)
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.
Did you know you can access the Native Plant Information Network with your web-enabled smartphone?
Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.
![](../_images/mr_smarty_plants_logo_web_200w.jpg)
rate this answer
![](../_images/star_00.gif)
Wednesday - November 26, 2014
From: Austin, TX
Region: Southwest
Topic: Planting, Erosion Control, Groundcovers, Shade Tolerant, Grasses or Grass-like
Title: O.K. to grow grass under a live oak?
Answered by: Guy Thompson
QUESTION:
Is it a bad idea to plant grass around a mature live oak? We have erosion issues and trying to keep mulch in the beds around the tree groves is a challenge, even with edging. Much of the native dirt has actually washed away over the past several years when we gave up on mulch and some of the roots are starting to become exposed. A landscaper has suggested putting grass up to the trees to help with erosion. Honestly, I wouldn't mind if the tree growth slowed, but I do want them to stay healthy and disease free.ANSWER:
Before planting anything you will need to confront the erosion problem that you have. Perhaps you could build swales or barriers to redirect rainwater away from the oak until your new plantings take hold in some freshly added soil.
Growing grass under a live oak will not harm the tree. The problem is finding a grass that will thrive in the tree's shade. Hopefully you have a high canopy that allows considerable light to reach the ground. There are no native turf grasses that do well in shade. However, there are several bunch grasses that would look nice under light shade. These grow too tall to stand foot traffic, but they can be quite attractive.
One grass that I grow in shade as a ground cover is Paspalum setaceum (Thin paspalum). It grows only a few inches high and the rather unattractive foot-tall seed heads can be controlled by mowing. If you can accept taller species, consider the following suggestions, taken from a previous Mr. Smarty Plants answer:
Bouteloua curtipendula (sideoats grama), the State Grass of Texas, 2-3 feet
Bouteloua hirsuta (hairy grama), 10-18 inches
Chasmanthium latifolium (Inland sea oats), 2-4 feet, a particularly attractive plant that grows well in deep shade
Elymus canadensis (Canada wildrye), 2-4 feet
Poa arachnifera (Texas bluegrass), 2-3 feet
Schizachyrium scoparium (little bluestem), 2-4 feet
You might also consider using sedges. They make very good groundcovers and they tend to be rather short. You can read about their use for lawns in Sedge Lawns for Every Landscape by John Greenlee.
Carex blanda (eastern woodland sedge), 1-3 feet
Carex cherokeensis (Cherokee sedge), 12-18 inches
Carex planostachys (cedar sedge), less than 12 inches
Carex texensis (Texas sedge), 10-12 inches
Finally, here are a few groundcovers that aren't grasses or grass-like, are less than 18 inches high and will grow in the shade or part shade. They are mowable. I attach extra images of these.
Calyptocarpus vialis (Straggler daisy)
Ruellia humilis (Fringeleaf wild petunia)
Seeds for many of these plants may be obtained at your local plant nurseries. Native American Seed is a particularly good source.
From the Image Gallery
More Erosion Control Questions
Plants for erosion control in arid region
September 29, 2008 - In semi arid south west (Phoenix), the drainage is managed by creating incised channels. Typically, the dirt channel can erode with even very low velocities of moving water. To reduce erosion therefor...
view the full question and answer
Grass for erosion control
July 19, 2008 - I have a very shaded sloped back yard. I have not been able to get grass to grow due to the shade. There are approximately twenty 30-40 ft. Oaks in the yard. The yard slopes toward the house. I wo...
view the full question and answer
Plants to prevent erosion on slope in Texas
June 19, 2010 - We have an erosion problem developing on the low side of a gently sloping hill. We are in clay soil at the base of the hill with oaks and pines. We have a right of way that is without trees forty fee...
view the full question and answer
Difficult slope in Tarrytown NY
March 03, 2009 - I hope you can help. Is there a way to plant some native shrubs and plants on a steep slope that is filled in some areas with rock without having to tier the slope? The section is approximately 50' w...
view the full question and answer
Need plants to cover hillside and control erosion in Woodbine, Kentucky
September 18, 2009 - I live in eastern Kentucky. I have a hillside that is full of weeds how do I get rid of the weeds and what can I plant to cover it. This hillside is not walkable. Is there some kind of vine ? There is...
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |