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
1 rating

Tuesday - June 07, 2011

From: Austin, TX
Region: Southwest
Topic: Watering, Drought Tolerant, Trees
Title: protecting native trees during drought
Answered by: Guy Thompson

QUESTION:

We are very concerned about our mature live oaks and cedar elms because they are so stressed due to the drought. We have lost several of our mountain juniper and I really don't want to lose our more valuable trees. I know slow deep watering is best, but how much water is that? Can you give me advise on how to water them that will do the most good?

ANSWER:

There is no question that even old, well-established trees are going to need some extra help during the kind of drought we are having right now. Many trees have been saved in past droughts by additional  watering in late summer. As the underlined article suggests, professional arborists suggest deep watering, and the amount of water applied would depend on your soil type, e.g., rocky or clay.  The trees might also benefit from additional fertilization.  Furthermore, rees suffering from drought stress are often more susceptible to insect and fungal attack.

This University of Illinois Extension website Dealing with the Drought affirms that watering even drought-resistant trees like the oak is essential. It points out that a 90 ft. oak tree will be a lot worse to lose than annual flowers or vegetables. We don't recommend watering at the base of the trunk, but watering farther out, with a hose or sprinklers, probably about every two weeks. An excerpt from this website will tell you why:

"Our 90-foot oak example could have roots at least 40 feet beyond the tree’s
drip-line. The same goes for most shrubs. So, apply water at the tree or
shrub’s drip-line, not at the trunk."

Those roots may be pretty deep, and part of the protection of the trees, but much of the root system is in the top 12 inches of the soil. So, putting the water out there helps to avoid fungus and rot at the base of the trunk.

 

More Trees Questions

Why all the acorns from Austin
November 03, 2010 - What's the explanation for the huge crop of acorns falling from my live oak trees this fall. Do you recommend I dump them in my composter or just throw them in the flower beds? Thanking you in adv...
view the full question and answer

Tree roots breaking surface in Allen, TX
March 09, 2009 - I live in Northern Texas, near Dallas. My questions concerns a tree in my front yard that now has roots that break the surface of the soil and grass. I would like to cover the roots. Should I cover...
view the full question and answer

Why is Rhus aromatica more deer resistant from Seattle
December 07, 2009 - I have a large area that I would like to cover with Rhus aromatica. My landscaper says that in his experience, Rhus typhina and glabra in this area are heavily browsed by deer. I noticed in your dat...
view the full question and answer

What can be planted under a pine tree in Detroit, MI?
April 22, 2008 - What type of plant would you suggest I plant under my big (Blue bruce) pine tree? It's about 25 ft high and the branches are trimmed to about 4 feet up, so it does get some light but mostly shade.I a...
view the full question and answer

Wildflowers that grow in woodlands
June 22, 2011 - Please tell me the names of wildflowers that grow under your oak trees in Texas. I am only familiar with those open meadow plants, not those that live under the deciduous trees. Thank you for your t...
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