En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - Problems with sophora secundiflora

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
1 rating

Saturday - April 19, 2008

From: Austin, TX
Region: Southwest
Topic: Trees
Title: Problems with sophora secundiflora
Answered by: Barbara Medford

QUESTION:

My mountain laurel is looking bad. It has lost of its leaves, especially on the lower part of the tree (it's about 7 feet tall) and many of the remaining ones don't look good - they are curled up and spotted. The spots could be from insect eggs. This is the second year this has happened. It continues to get healthy new growth, however, and it bloomed some this year. I planted it about 20 years ago. It gets full sun. Several other mountain laurels close to it are perfectly healthy. Is this some kind of insect infestation? What should I do to care for it?

ANSWER:

The first possibility is that the leaves are chlorotic; that is, they don't have enough chlorophyll, which can cause black spotting between veins in the leaves. Plants can become chlorotic because the soil in which they are growing is so alkaline that the plant has difficulty extracting the iron that it needs from the soil. In the Austin area, particularly with other mountain laurels growing nearby, it seems unlikely that too much alkalinity is the problem. However, chlorosis in the Sophora secundiflora can also be caused by overwatering or watering too shallowly. This particular plant requires very good drainage and is accustomed to growing on limestone shelves or in very rocky soil. If your affected mountain laurel is in a low spot, a spot that accumulates moisture from runoff, or is watered by a sprinkler system, but not thoroughly, that could be causing the symptoms you are observing. Check the drainage on that tree; they need only be watered (if there has been no rain) every two to four weeks, but need to be deeply and thoroughly watered then. We think this is probably the most likely culprit.

We found several references to the genista caterpillar, apparently the larval stage of the Genista moth. Read this article on the Sophora Worm from the Maricopa (AZ) County cooperative Extension Home Horticulture site and see if any of the symptoms match the ones you are observing. Apparently, just picking off the caterpillars and/or destroying the webs that are spun by them controls that problem. If, upon close examination, you feel this is your problem, the website says you probably don't need to worry about it, but does give suggestions for control if the problem becomes severe.

 

 

More Trees Questions

Need help with my 25 yr old Mountain Ash in Clinton Township, MI.
July 11, 2011 - For the first time our 25yr old mountain ash tree has dying branches, we removed one branch and it seems to have spread to other branches? What should we do?
view the full question and answer

Killing regrowing shoots of a downed hackberry tree
June 28, 2013 - Hackberry plants won't die. You and others have suggested to cut the suckers or saplings to get rid of them. Over the years I have continued to cut the same saplings and the only thing I have now ar...
view the full question and answer

Disappearance of leaves on desert willow in Tucson AZ
August 08, 2009 - We have a Lois Adams Desert Willow (Tucson, Az). The leaves will pump out and then a day or so later, all of the leaves are gone. The only bugs we've seen on it are very, very small ants. Could this ...
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

Revegetating a hillside in western Washington state
October 10, 2012 - Removing several downed trees across my dock demolished the native plants growing on the hillside and the contractor pulled out their remains. The area faces east on an open freshwater bay. Close to...
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.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center