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?


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
3 ratings

Saturday - February 02, 2008

From: Rockport, TX
Region: Southwest
Topic: Trees
Title: Protection of live oak trees from covering by concrete patio
Answered by: Nan Hampton


I am thinking about pouring a large cement patio around my live oak trees in my yard. I live in Rockport Tx. How far should the edge of the cement be, from the base of the tree? Will the patio kill the trees?


Roots of trees generally extend at least as far out as the shadow of the canopy of the tree. This area is referred to as the Protected Root Zone (PRZ). Covering this area with concrete is likely to cause the death of the tree by physically damaging the roots and by inhibiting oxygen and water from reaching the roots. Additionally, the roots of the tree have the potential to damage/crack the concrete as they grow trying to reach water and oxygen.

There are a number of permeable paving materials that you might consider instead of concrete. These include such materials as paving bricks, flagstones or patio blocks as long as they are laid without mortar. You can find more types of permeable pavers here. Another possibility is a raised wooden deck that could go right up to the edge of the tree with no harm as long as its foundation didn't damage the roots of the tree.

You can read more about protecting trees from damage during construction projects and advice about placement of pavement in the area of trees in Landscaping Around Established Trees from University of Nebraska-Lincoln Extension Service and Protecting Trees from Construction Damage: A Homeowner's Guide from the University of Minnesota Extension Service.

You can find a list a Landscape Professionals near your area who could advise you on permeable paving materials in our National Suppliers Directory. You might also try your local library or bookstores for books on alternatives materials for patios (e.g., Taunton's Deck & Patio Idea Book or Sunset Ideas for Great Patios and Decks).


More Trees Questions

Trees with white blossoms in Crockett, Texas
March 21, 2015 - What are the trees that are blooming just East of Crockett Texas (off of Hwy 21) right now - fairly large trees - multitude of white blooms - almost like a wild plum or pear, but tree seems too large?...
view the full question and answer

Tree (evergreen) to grow in area with high water table
March 27, 2011 - Dear Mr. Smarty Plants, We live in central Austin, Tarrytown specifically, just blocks from the aptly named Spring Lane. (sometimes we hit water in our back yard within 2 feet of the surface.) We los...
view the full question and answer

Deciduous shade tree for Inland California dry hills
July 26, 2011 - What type of tree would work well in our back yard? We're looking for a deciduous tree that doesn't grow too tall, maybe 20'. We'd like it to have spreading branches to provide shade during the su...
view the full question and answer

Dormancy in Pin Oaks without water in Del Rio, TX
August 02, 2011 - Can Pin Oak trees go dormant without enough water? If so how long can they live that way? Can they be brought back to producing leaves? If yes, then what do I need to do besides giving them water. I d...
view the full question and answer

Proper time of year to plant evergreens in New York
October 25, 2008 - Dear Smarty Plants, Is it too late to plant evergreen Thuja, blue spruce and firs in Cleveland, New York? Vicki
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center