En Español

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

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

rate this answer
Not Yet Rated

Thursday - May 20, 2010

From: Tucson, AZ
Region: Southwest
Topic: Transplants, Trees
Title: Will Texas Mountain Laurel roots damage pipes in Tucson AZ?
Answered by: Barbara Medford


We have a Texas Laurel tree in our back yard,and it is doing fine, and we are are planning to put another one in the front yard close to the house will the root system attack our pipes ? no septic system.


Do you mean a Texas Mountain Laurel, Sophora secundiflora (Texas mountain-laurel)? We will assume that is the tree you are considering. We were concerned when we discovered that it is not listed as native to Arizona in our Native Plant Database; however, we then found this article by Master Gardeners on a Pima County Cooperative Extension website, Texas Mountain Laurel. You say you already have one in your yard, so obviously they must be able to live in Arizona.

When you inquire about the roots of this tree attacking your pipes, are you referring to sewer pipes or water lines? The Mountain Laurel has a sparse root system but a deep taproot, an adaptation for survival in desert conditions. Once upon a time, when most sewer lines were clay, like the clay pots,  invasive roots did, indeed, break them up and cause major problems. Nowadays, both water and sewer pipes are more often a heavy-duty plastic material, and don't have as much trouble with roots. The mountain laurel is very difficult to successfully transplant because of that taproot-damaging it in transplanting can be fatal to the tree. We would suggest that you first acquaint yourself with the location of the pipes you are concerned about, including the depth they are in the ground.  You did not say if you intended to plant seeds or purchase a tree for transplanting, but it would be a good insurance policy to not dig the hole for the tree directly over those pipes. The resources we searched made no mention of intrusive roots from this tree, just cautioned about the difficult of transplanting the tap root, as well as warning that the tree grows very, very slowly.

From our Native Plant Image Gallery:

Sophora secundiflora

Sophora secundiflora

Sophora secundiflora

Sophora secundiflora





More Transplants Questions

Possible transplant shock in recently planted Anacua in San Antonio, TX.
February 10, 2011 - I planted an Anacua tree from a nursery this past November. The tree I purchased was about 6ft tall and was a leftover from the spring. The roots were pretty wound up inside. After shaking the roots l...
view the full question and answer

Peeling bark on red oak in Plano, TX
April 08, 2010 - I have a red oak that was planted 2 years ago. The trunk is approx. 5 in around. The bark around the bottom of the trunk is peeling off. At first we thought it was rabbits so we put some rabbit gua...
view the full question and answer

Privacy plantings in Texas
August 16, 2008 - Our home currently has a 4' chain fence. We are a family of 7 with younger aged children and are looking for more privacy. In lieu of a replacement fence, what would you recommend planting to provi...
view the full question and answer

Transplanting crabapple tree from root sprouts
March 24, 2005 - I have a Crabapple tree that is sending up sapling shoots. Can these be dug up and planted?
view the full question and answer

Smarty Plants on daylilies
July 29, 2003 - I have a number of Daylilies that are rapidly multiplying in my flower bed. If I relocate some of them to the field behind my house, will they crowd out the native wildflowers?
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center