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?


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
Not Yet Rated

Friday - May 30, 2008

From: Austin, TX
Region: Southwest
Topic: Pests, Shrubs
Title: Sap drips from Sophora secundiflora
Answered by: Barbara Medford


We have an old Mountain Laurel (sophora secundiflora) about 20 ft tall. It blooms pretty well and seems healthy. We are wondering why it drizzles a non-sticky sap in tiny drops. Hold out your hand and you think it's starting to rain. We hope it's a sign of good health, and we are very curious why the plant does this.


That sounds an awful lot like aphids. Anyone who has ever had to park their car under a tree that has aphids can talk to you about the mess it makes. And every reference to Sophora secundiflora (Texas mountain-laurel) that we found said that it was not threatened by any serious pests and diseases. Don't you hate when they say that and you KNOW there is a problem?

Getting back to the possibility of aphids. The University of California Integrated Pest Management has an excellent website on aphids. In the article, you'll find ways to identify the presence of the little bugs, when they may be more or less numerous, and non-chemical ways to treat them without damaging the beneficial bugs that eat aphids. One note you will particularly appreciate is that aphids do not do well in very hot temperatures. So, since it looks like this is going to be a really hot summer, maybe that's a good thing.

We found another critter that targets Mountain laurel, but is not considered serious except in very young, new trees. The Maricopa (Arizona) County Extension Service has published an article on the Sophora worms, Uresiphita reversalis.



More Pests Questions

Problem with leaf cutting bees in Houston, TX
December 08, 2014 - I have four Arapaho crepe myrtle trees in my backyard and two have leaves, especially the young leaves, being eaten by something. I do not see ants of beetles on the leaves and have not seen any bees ...
view the full question and answer

Problem with leaves of Texas Ash in Austin
May 21, 2012 - We purchased a 3' to 4' Texas Ash in March 2012. The past few days I noticed new leaves at the top are curled under, have a milky substance on them, and more than a few ladybugs on them. What is thi...
view the full question and answer

Georgia Monocots for Dodder Infested Location
September 02, 2015 - I have a 12'x12' area where we planted carrots, and we got a surprise - dodder! Next year we planted corn - no dodder! This year we planted cosmos, and behold, we had dodder. I understand monocot...
view the full question and answer

Doodlebugs in dead area of Coral Bean from Houston
April 10, 2013 - I have a Firemans coralbean tree about 5 years old. I discovered yesterday in the middle of the tree there is some deadwood where we have pruned out branches. A couple of the branches were filled with...
view the full question and answer

White spotting on prickly pear cactus
July 28, 2015 - Hello- I have large prickly pear cacti and just noticed large white spotting on some of the leaves. I also see some black bugs and apparently they are the problem.They are about 1/4" long. How can I ...
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.
© 2015 Lady Bird Johnson Wildflower Center