Native Plants

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?

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

4 ratings

Thursday - August 31, 2006

From: Helotes, TX
Region: Southwest
Topic: Trees
Title: Possible wilt disease in mountain laurels
Answered by: Joe Marcus

QUESTION:

Three of about 24 of my mature mountain laurels died suddenly, the leaves turned brown almost overnight, scratching the bark revealed no green tissue, the small branches practically cracked when bent, the leaves went from green and healthy to dry and brown in about three to four days, the plant seemed to have just dried up. I do not believe they were over or under irrigated as other healthy mountain laurels remain immediatly adjacent to the dead ones. I detected no caterpillar damage. Any ideas what happened?

ANSWER:

Texas Mountain Laurel, Sophora secundiflora is famously resistant to most pests and diseases; the one major exception being the Genista caterpillar which attacks the leaves. However, the phenomena you described are pretty classic symptoms of a wilt disease. Wilts are usually caused by fungal pathogens invading and clogging vascular tissue in roots or stems of plants, thus the sudden decline of the plant. Species of fungi within the genera Verticillium and Fusarium would be the most likely cause of the disease, but Texas Mountain Laurel is not known to be particularly susceptible to any of them.

There are other possibilities, but without actually examining the plants, it would be difficult to rule any cause either in or out. You should contact your county agricultural extension agent for information on having samples from your dead plants tested to determine the cause of the problem.

Native Plants

Ask Mr. Smarty Plants

rate this answer

Thursday - August 31, 2006

QUESTION:

ANSWER:

More Trees Questions