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

Replacing Weeds with Native Plants in Dallas Area
May 29, 2011 - I have a large oak tree in my front yard and lots and lots of miscellaneous weeds (clover, chickweed, stickers, etc.). I am wanting to grow grass in my front yard, that is shaded pretty much most of t...
view the full question and answer

Identity of tiny green spiders found in Sego lilies
July 14, 2015 - Hi - I'm wondering if you can identify for me the name of the tiny green spiders that can be found inside Sego Lilies (Calochortus nuttallii). I have a photo if that would be helpful. Thanks!! Ca...
view the full question and answer

Galls on live oak tree in Austin
December 12, 2013 - I live in Austin, and have a 13 year old live oak in my yard. It has developed little spheres, kind of like green peas, on the underside of the leaves. What is it? Is it harmful? Is there somethin...
view the full question and answer

Weedy buffalo grass from Dripping Springs, TX
March 07, 2013 - I have a buffalo grass lawn. It is thin and filled with weeds. I would like to find a solution to improve my lawn. I prefer a native grass but I need to be able to control the weeds and I am not ph...
view the full question and answer

Possible webbing bark lice on oak tree
August 08, 2008 - We live near the Center and have a large live oak tree in our yard. Recently the lower trunk has been covered with thin, white weblike material (not sure if spider web). What could this be and is it d...
view the full question and answer

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