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
6 ratings

Saturday - February 07, 2009

From: San Diego, CA
Region: California
Topic: Trees
Title: Tree that will not interfere with hardscape in San Diego
Answered by: Barbara Medford

QUESTION:

I am looking for a small tap root tree that will reach max height of 20-25 ft. The area is only about 4 to 6 ft. to the house slab or driveway which I need to be very careful so it doesn't crack the driveway or house slab or get into the sewer or water pipes. Tree must be for San Diego, CA area. Be able to handle water has it will be hit by 2 yard sprinklers. Prefer green year round with no berries or flowers as I don't want the mess. Any suggestions will greatly be appreciated.

ANSWER:

That would be a find for gardeners everywhere, a tree that can be planted close to the house slab, driveway and sewer lines without roots ever interfering with those items. Unfortunately, it doesn't exist. "Taproot" is really a misnomer, because any tree is going to spread some roots out, most of them 3 to 6" below the surface, because that is where the water and nutrition are. They also need those roots for balance. In a high wind, a true taproot tree would be top-heavy and highly vulnerable to being blown down. And, we don't know how to tell you this, but almost all plants except ferns are going to have some kind of blooms and seeds (berries), because all plants are programmed to reproduce; the blooms and seeds are their reproductive process. Here is some of the research we did, hoping to find a fit for your requirements. 

Iowa State University Forestry Extension Tree Roots. According to this website, taproot trees include hickory, walnut, butternut, white oak and hornbeam, with only Juglans californica (Southern California walnut) being native to California. All of these tend to be much larger than you are looking for, and all are nut or acorn trees, which means lots of mess, year round. Trees that do develop a taproot must be planted when they are very young, as damage to the taproot can mean death to the tree.

From Florida Plants Online Dispelling Misperceptions About Trees:

"Most trees do not have taproots. In sandy, well-drained soils some trees such as oaks and pines develop deep roots directly beneath the trunk. These are commonly called taproots. Many trees never develop tap roots. When the water table is close to the surface or when the soil is compacted, taproots do not develop."

"Taproots generally do not form on trees planted in our urban landscapes. Roots grow far beyond the edge of the branches. Frequently, roots extend from the trunk as far as the tree is tall. Roots and shrubs planted in a landscape grow to 3 times the branch spread within 2 to 3 years after planting."

You might even consider a bed of blooming plants for this area, as they will have shorter roots, or perhaps some tall native grasses. You can use the same Recommended Species section and put "Herbs" (herbaceous flowering plants) or "Grasses/Grass-like Plants" under Habit. 

What we will try to do is find an evergreen shrub, probably not as tall as you are thinking, that will have less extensive roots and still provide some color to the landscape. The water from the sprinklers could also be problematic, as it might cause molds or fungi to attack the plant. We will go to our Recommended Species section, click on Southern California on the map, NARROW YOUR SEARCH by selecting on "Shrub" under Habit. Since we don't know if you have sun or shade, we will leave you to do the same thing and make other selections appropriate to your situation. If you find something that you feel will work for you, but have difficulty locating it, go to our Native Plant Suppliers section, type in your town and state in the "Enter Search Location" and you will get a list of native plant nurseries, seed companies and landscape and environmental consultants in your general area.

Ceanothus velutinus (snowbrush ceanothus) 

Cocculus diversifolius (snailseed)

Cercocarpus montanus var. minutiflorus (smooth mountain mahogany) - pictures

Dasiphora fruticosa ssp. floribunda (shrubby cinquefoil)


Ceanothus velutinus

Comarostaphylis diversifolia

Dasiphora fruticosa ssp. floribunda

 

 

 

More Trees Questions

Non native crape myrtle changing bloom colors in Sonora CA
September 05, 2012 - I have a Red Rocket Crape Myrtle that was planted a little over a year ago. Last year the bloom was a beautiful deep red and this year it is a Mauvie pink. Is there something I can do to bring it back...
view the full question and answer

Planting live oak trees in summer in Austin
June 09, 2011 - We would like to plant a few live oak trees in our front yard for shade and animal protection. As it is very hot and dry right now, can we plant now? If not, when?
view the full question and answer

Need a tree to grow in the middle of a retention pond in Pennsylvania
June 03, 2010 - I have a shallow retention pond in my yard in South Eastern Pennsylvania. The pond is used for rainwater runoff and also for natural springs that are located below the surface. If I plant a tree in th...
view the full question and answer

What is causing leaf drop on oak in Morgan Hill CA?
June 23, 2010 - Dear Mr Smarty Plants: We have a large, young Valley Oak (about 20 yrs) which is dropping leaves even now in early summer. I have a feeling that the problem might be an invasive weed that is flourishi...
view the full question and answer

Tree to plant by pool replacing mulberry in Las Vegas
January 18, 2009 - I am looking for a tree to plant between my house and pool. We just cut down a mulberry that was here due to its invasive root system. Are there any plants that can tolerate Vegas weather, provide a...
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