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

Wednesday - November 09, 2005

From: Lexington, TX
Region: Southwest
Topic: Diseases and Disorders
Title: Cotton root rot in Purple Sage, Leucophyllus frutescens
Answered by: Joe Marcus

QUESTION:

We had three Purple Sage shrubs in our front yard. They did very well for about three years and then this past year they just died. From what I have read they are pretty hardy so we are really stumped as to what happened to them.

ANSWER:

 

Purple Sage, Leucophyllum frutescens is also known as Cenizo, Texas Ranger, Texas Sage, Barometer Bush and Silverleaf. It is a tough-as-nails shrub native to south Texas.

 

Purple Sage is highly resistant to most insect pests and diseases. However, it is susceptible to Cotton Root Rot (Phymatotrichopsis omnivora) in poorly drained soil, in over-watered landscapes or during wet seasons. Once Cotton Root Rot, also known as Texas Root Rot, has infected one plant in a landscape, the pathogen stays in the soil and will infect other susceptible plants that replace it. The much-used Red Tip Photinia, Photinia xfraseri is particularly susceptible to Cotton Root Rot and is responsible for many of the occurrences of the disease that we see.

 

To positively identify Cotton Root Rot, it is best to pull a dead plant out of the ground, shake off as much soil as possible away from your landscape, and take the plant -- roots and all -- to your county agriculture extension office. For more information on this particularly pernicious fungal disease, see this article on Diseases of Urban Landscapes.

 

More Diseases and Disorders Questions

One wax myrtle declining in Austin
April 20, 2011 - I have 3 wax myrtles in a row; two are doing fine and one is looking "sad". It is thinning and when I checked a few branches they were dead, I pruned it and it was dead. I have had the trees for 7 y...
view the full question and answer

Ostrya virginiana Compatible with Juglone
May 17, 2015 - Is Ostrya virginiana sensitive to juglone?
view the full question and answer

White fuzz on Christmas tree from Lewisburg PA
January 04, 2011 - Our Canaan fir Christmas tree is now coated with white fuzz after being up for 4 weeks. The fuzz looks like spider webs, but it is also in clumps around the needles. When you rub your finger on it, ...
view the full question and answer

Ailing Lacey oak in Austin
August 09, 2010 - I have a five-year-old lacey oak that is about 5 feet tall. Last last spring it became infected with oak phylloxera, which was initially misdiagnosed. I treated it with Neem oil several time but this ...
view the full question and answer

Mice eating seeds put out for birds
June 02, 2008 - I love feeding the wild birds and put out seed in our backyard. Now, I have a family of mice eating the seed and they are living in the trunk of our elm tree! How can I get rid of them without killi...
view the full question and answer

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