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
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

QUESTION:

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.

ANSWER:

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

Cupressaceae dying in Suffolk Co.NY
October 20, 2012 - I have noticed that all of my Cupressaceae (& others I see in my area) are dying. They turn yellow, then rust & brown til they are everbrowns. what is going on?
view the full question and answer

Do Deer Eat Orchid Trees?
March 08, 2013 - I have planted three anacacho orchid trees, however we have a lot of deer around us. Is this a tree they will want to eat? Do you have any ideas to keep deer away?
view the full question and answer

Problems with non-native yellow lantana from Elgin TX
June 17, 2012 - Why do my yellow lantana buds turn brown and do not open fully? The sprinkler system does not spray onto the lantana.
view the full question and answer

How are NPIN Deer Resistance Ratings Determined?
May 06, 2014 - If your plant data-base (which is the best thing since sliced bread!) is silent on the degree to which a plant is deer-resistant, does this mean you just don't have enough information to make the cal...
view the full question and answer

Fighting ants and bugs in Richardson TX
September 01, 2010 - Before my blue fall asters and my Clara Curtis (perennial) mums bloom in a few weeks, what can I do to help prevent the ants and other bugs from eating them to death- so I can enjoy them a bit longer ...
view the full question and answer

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