Host an Event Volunteer Join Tickets

Support the plant database you love!

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
Not Yet Rated

Tuesday - August 16, 2011

From: Brenham, TX
Region: Southwest
Topic: Diseases and Disorders, Pests, Watering, Trees
Title: Oak tree with browning leaves in Brenham TX
Answered by: Barbara Medford

QUESTION:

I have a large oak tree in my small back yard. I also have a sprinkler so the tree has been receiving some water. Nevertheless, some of the leaves are turning brown in patches. Would drip watering over days help this situation due to the drought?

ANSWER:

This year, everything is turning brown, some in places like your oak tree, and some all over, indicating a very dead plant. There are all kinds of diseases and pests of trees or, more specifically, of the oak that could be causing this. Here is a paper from Forest Health Protection, Southern Region on Oak Pests. Since we are neither entomologists nor plant pathologists we cannot diagnose the specific problem, especially without seeing it.

But, because of the extreme weather in Central Texas, we are betting on the heat and drought being the source of the problem. Before you even try to find out if insects or disease are causing the browning, we would definitely recommend watering more. Remember how far out from the trunk those roots are growing-at least as far out as the drip or shade line, and usually two to three times that. Drip watering of a tree is really only effective when the tree is very small and newly planted. In that situation, we suggest you push a hose down in the soil and let the water drip slowly until water rises to the surface, at least twice a week during hot, dry weather. For a large mature tree, you need to get water farther out and you probably couldn't get a hose in the ground for drip watering there. Use the sprinkler, moving it around to water each area where roots probably are, and leave it in each position long enough to really wet the soil. Again, twice a week.

The leaves that are brown will not turn green again, it will soon be time for the oak to drop leaves anyway. But if you start providing water to the little rootlets all up and down the length of the main roots, the tree will have the energy to put new leaves on in the Spring season.

 

More Diseases and Disorders Questions

Fungus type problem on native blackeyed susans in Ohio
August 20, 2008 - I have black eyed susans that have recently developed a black fungus type problem in the bottom and on the leaves. The flowers are now wilting and dying. What is this and how can I stop it from possib...
view the full question and answer

Something eating Arizona ash in Gilbert AZ
May 11, 2011 - Something is eating my Arizona ash tree. what should I spray on it?
view the full question and answer

Problems with rock rose in Austin
June 10, 2013 - Hi Mr Smarty Pants, We have a Texas Rock Rose which is growing next to our gravel path in Austin, with grass growing under it. In the last week, it has stopped blooming suddenly, and all the leaves h...
view the full question and answer

Yellowing leaves on non-native globe willow in Las Cruces, NM
June 26, 2010 - I live in Las Cruces, NM. I have a good size globe willow tree. The leaves are turning yellow and brown dryness at tips and leaves are falling off. Does it just need water?
view the full question and answer

Corona de Cristo, guest or pest?
July 12, 2008 - We have had two recent speakers at the Austin Butterfly Forum with differing views as to whether Passiflora foetida is invasive in Texas. One believes that it's well-behaved and a a great butterfly ...
view the full question and answer

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