Native Plants
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.
rate this answer
Tuesday - September 04, 2012
From: Austin, TX
Region: Southwest
Topic: Problem Plants, Erosion Control
Title: Exposed Tree Roots in Austin
Answered by: Brigid & Larry Larson
QUESTION:
I have a large ash tree with a lot of mud at the top of a sloping yard. I want to build a small retaining wall with the ground leveled above. This would entail covering exposed tree roots with 4-18 inches of dirt. Will this hurt the tree?ANSWER:
Mr Smarty Plants is a bit mixed on your question. Common knowledge has it that it is harmful to a tree to cover its roots, yet if the roots are exposed anyway it is tempting to cover them a bit.
This article from the Colorado Extension describes the root mass, both that it extends beyond the tree crown and that the majority of the action is within 6 to 24” of the surface.
The issue with covering the roots involves compaction of the soil. The article above states ”Changes in soil depth around trees can also cause injury to root systems. The addition of only 4 to 6 inches of soil over a root zone drastically reduces the amount of oxygen and water available to the roots”
A great solution to your desire is to build a “Tree Well”, where the roots are covered with very coarse rock or mulch to preserve their air and water access. This publication from the West Virginia Extension states 18” as the depth where plain dirt fill would be too deep. It gives excellent recommendations on building a tree well.
From the Image Gallery
More Problem Plants Questions
Elimination of Whitemouth dayflower in Dothan AL
March 18, 2009 - I am infested with Widow's Tears in my yard. I would like to get rid of them. Can you tell me how?
view the full question and answer
Germination of Sophora seeds, and Dodder identification in Kingsland, TX.
May 02, 2012 - Our Mt. Laurel has just produced seeds. Can those be scarified and planted now or do they have to dry out.
Also what is the stringy orange substance that gets on bluebonnets and other wildflowers ...
view the full question and answer
Removing Persimmon plants from the base of Live oaks
October 15, 2015 - I live in Bastrop county and have hundreds of Texas wild persimmons at the base of my huge oak trees. Should I cut some of them? I am worried they are taking up water my oaks need. I like them but do...
view the full question and answer
Shoots sprouting around base of liveoak tree
April 18, 2008 - I have a Live Oak that was planted in my yard about 15 years ago. In the last several years, small shoots have been sprouting up around the tree base, are getting more dense and spreading into the gr...
view the full question and answer
Skin Reaction form Cochineal on Prickly Pear
February 16, 2015 - I have severe burning and peeling skin on pads of fingers after touching "white stuff" on a prickly pear. White stuff tuned purple then burned skin even after washing hands. Skin has been cracking a...
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |