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 Shrubs Questions

Replacement for boxwoods in Ohio
February 26, 2014 - I want to replace my boxwood plants but I don't know what would be a good replacement. I have a hydrangea plant that is in the middle and I would like something to go on each side of the hydrangea. I...
view the full question and answer

Plants to prevent erosion on slope in Texas
June 19, 2010 - We have an erosion problem developing on the low side of a gently sloping hill. We are in clay soil at the base of the hill with oaks and pines. We have a right of way that is without trees forty fee...
view the full question and answer

Native shrubs for wildlife santuary in Georgia
March 27, 2009 - We live south of Atlanta, GA and are trying to have our backyard certified as a Wildlife Sanctuary. Can you suggest native shrubs that thrive in partial sun, are habitats for bird and are deer resist...
view the full question and answer

Shrubs to stabilize steep slope in California
February 03, 2010 - Suggest shrubs to stabilize steep bank that are drought resistant and resistant to too much rain. Cape honeysuckle? oleander? bottle brush? What?
view the full question and answer

Plantings for a slope from New Carrollton MD
June 27, 2012 - My house (Maryland, near DC) sits at the bottom of a south facing slope. The soil is very heavy clay. The grade is about 1:20 for about 100 feet (with a steeper part at the top). Part of the hill is i...
view the full question and answer

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