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?

Share

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
Not Yet Rated

Saturday - June 07, 2014

From: Fort Worth, TX
Region: Southwest
Topic: Planting, Problem Plants, Shrubs, Trees
Title: Need for smaller tree with less invasive roots from Ft. Worth TX
Answered by: Barbara Medford

QUESTION:

The sycamore in the front yard has developed roots larger than the branches. They have decided that the water and sewer lines are perfect to acquire their water from. For this reason it will be coming down in fall. Is there a smaller ornamental tree that will not encroach on the buried lines or the house foundation?

ANSWER:

This is an ongoing problem for gardeners. In hot Texas, everyone longs for shade and big-leaved, relatively fast-growing sycamores sound like a blessing UNTIL the roots start messing up underground equipment. You have made a wise decision to take down your Platanus occidentalis (American sycamore), which, by the way, according to this USDA Plant Profile Map, is native to the Tarrrant County area.

Our general advice on roots is that the roots of a tree will extend out at least 2 to 3 times farther than the dripline or shade line of the tree. Our experience is that  roots can be very invasive, often above the soil surface, and interfering with hardscape such as sidewalks, patios and, yes, house foundations, not to mention water and sewer lines. If you follow the plant link Platanus occidentalis (American sycamore) to our webpage on the tree, you will find these statements:

"The American sycamore is a wide-canopied, deciduous tree, 75-100 ft. tall, with a massive trunk and open crown of huge, crooked branches."

"A shade tree, Sycamore grows to a larger trunk diameter than any other native hardwood. The present champions trunk is about 11 feet (3.4 m) in diameter; an earlier giant was nearly 15 feet (4.6 m)."

So, imagine 2 to 3 times that much root material below the ground and your underground lines don't stand a chance. In a large field or open landscape, it would be lovely. In a small city lawn it is a nightmare. Many of our visitors trying to avoid this sort of problem ask us for "taproot" trees, operating under the impressions that a taproot goes only straight down and does not interfere with other hardscape. Here is a previous Mr. Smarty Plants answer with respect for selections of taprooted trees. That answer is from Denison TX, in Grayson County not far from Tarrant County, so the suggestions made should still apply. However, please note this paragraph from that answer:

"Once the tree is planted and begins to mature, the distinctions between the root types become less pronounced. Then, the depth and lateralness of the roots is greatly dependent on the soil condition. Highly compacted soils, soils with low oxygen content and soils where the water table is near the surface are not likely to produce a strong tap root. Their roots are more likely to be lateral and located very near the surface with the majority of the roots located in the top 12 inches of soil. Also, it is important to realize that the spread of the roots can be at least 2 to 4 times greater than the drip line of the branches.

So, bottom line, you may need to not only modify the size of replacement plant for your sycamore, but perhaps the type. There are shrubs that will have less intrusive roots and provide greenery and bloom in your garden, but not shade. It's a hard choice, but what's it going to be? Sewer lines or shade? Here are some shrubs from our Recommended Species for North Central Texas list:

Anisacanthus quadrifidus var. wrightii (Flame acanthus)

Callicarpa americana (American beautyberry)

Ilex vomitoria (Yaupon)

Mahonia swaseyi (Texas barberry)

Salvia greggii (Autumn sage)

 

From the Image Gallery


Flame acanthus
Anisacanthus quadrifidus var. wrightii

American beautyberry
Callicarpa americana

Yaupon
Ilex vomitoria

Texas barberry
Mahonia swaseyi

Autumn sage
Salvia greggii

American sycamore
Platanus occidentalis

American sycamore
Platanus occidentalis

More Problem Plants Questions

Desert Willow Roots from Lubbock, TX
September 18, 2014 - I have a very, very happy Desert Willow that has grown larger than we expected and is probably too close to the house. Do I need to worry about a cracked foundation or pipe problems? Thanks!
view the full question and answer

How Can I Tell an Invasive Thistle from a Native
May 01, 2012 - Mr Smarty Plants, I have some thistles coming up in my yard. I'd like to keep them if they are native, but not if they are invasive or non-native. How can I tell? My yard is a wild area in West Lak...
view the full question and answer

Controlling sedge in vegetable garden in Mississippi
August 03, 2008 - I have a veg. garden surrounded by Purple Sedge. The nut grass has been contained/eliminated by replacing all dirt 1' down. Now the surrounding sedge is beginning to creep inward infesting the gard...
view the full question and answer

Toxicity of catalpa wood?
June 05, 2012 - Is the sawdust from cutting up a catalpa tree or the smoke from burning the wood toxic? Thank you,
view the full question and answer

How to get rid of nut grass from San Antonio
March 22, 2011 - We just had a house built on a lot that was mostly rock. The small back yard has a berm on which they brought in soil then mulched it. Now we are getting all sorts of weeds through the mulch, what my...
view the full question and answer

Smarty Plants's Facebook profile 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.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center