Rent Shop Volunteer Join

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

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
1 rating

Tuesday - August 02, 2011

From: Del Rio, TX
Region: Southwest
Topic: Watering, Drought Tolerant, Trees
Title: Dormancy in Pin Oaks without water in Del Rio, TX
Answered by: Jimmy Mills

QUESTION:

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 don't wont to cut them down if they have a chance of coming back. Thank you for your help! :)

ANSWER:

The short answer is yes, but they can also die without enough water.

But first, lets learn more about Pin Oaks Quercus palustris (Pin oak) . Clicking on this link takes us to its NPIN page, where we find that it is  a handsome lawn tree with shallow fibrous roots and high water use. Next, scroll down the page to the Additional Resources Box and click on the plant name beside USDA. This brings up the USDA Plants Profile page with a Distribution Map that indicates that Pin Oaks do not occur naturally in Texas. So we seem to have a tree in the wrong place, and perhaps, running out of time.

Plant dormancy is a survival strategy (see link)  that allows plants to live through unfavorable conditions. We most often think of it in the Fall where a series of programed processes take place that get the plant  ready for the freezing weather of winter. The most obvious results are the change of color of the leaves before they fall from the tree. The changing of the length of days and nights seems to be the environmental cue that triggers these changes.

Drought can also trigger dormancy as a result of stress on the plant due to a lack of water. One of the important processes that is going on in the leaves of the plant is photosynthesis which absolutely requires water. When water is scarce, the plant attempts to conserve water, and this can happen in at least three ways: the leaves can wilt, they can turn brown, or they can fall off. All of these shut down photosynthesis which reduces the demand on the roots for water.

What is the situation with your Pin Oaks? Are the leaves brown, or have they fallen off?  Before you proceed, you need to determine if the trees are still alive by applying what I call the “thumb nail test”. Locate a young thin  branch on the outer part of the tree, and scratch some of the bark off using your thumb nail. What you are looking for is green tissue. If you find some, that’s good news. If you don’t  move further down the stem and try again. Continue this until some green tissue is found. You’ll of course reach a point where the bark is too thick to scratch off with your thumb nail. If you haven’t found green tissue by this time, the prognosis is not good.

But let’s be optimistic! I’m including links to articles explaining dormancy, caring for trees in a drought situation, and watering tips to help you nurse your trees back to health.

Dormancy

   University of Alabama Extension

Tree Care

   centraltexastreecare.com

   Colorado State University

Watering

   University of Illinois





 

More Drought Tolerant Questions

Groundcover and Butterfly attractants for LaRue Texas
May 02, 2012 - LaRue, TX - Would like a native low growing plant as a groundcover. I would like it for six+ hours of sun, drought tolerant, and ones that butterflies might enjoy, while deer won't. Some winter int...
view the full question and answer

Narrow strip of groundcover from Sonora TX
April 29, 2013 - I have an area that is right under my patio about 12 feet by 1 ft. I'm looking for something to plant in there. It has afternoon sun, morning shade. I live in SW Texas so it is hot. but would like so...
view the full question and answer

Groundcover for Shade in Spicewood
September 16, 2015 - We live in Spicewood area in Austin, TX. Our front yard is yellow almost all summer, I was thinking of replacing lawn with a ground cover which can live on once a week sprinkler and no mowing. Also th...
view the full question and answer

low-growing evergreen shrubs for thin soil
March 05, 2012 - Thanks to the winter freeze, we'll be starting fresh with the plants in the bed along the front of our house. The bed is about 13' long and faces the west, so it gets afternoon/ evening sun but no ...
view the full question and answer

Drought-tolerant turf for Southern California
April 23, 2015 - Is it possible to grow Habiturf in Riverside, California, in the area of UC Riverside? The climate is similar to the desert areas or Arizona, just slightly cooler in the Summer. If not, is there a d...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.