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?

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
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 - October 06, 2007

From: Burke, VA
Region: Mid-Atlantic
Topic: Diseases and Disorders, Pests, Trees
Title: Possible disease on Eastern Redbud
Answered by: Barbara Medford

QUESTION:

Our Eastern Redbud appears to be suffering from our recent drought. The leaves are turning brown in July/August on a few branches. A few black spots appear on the leaves before they turn brown. Other smaller Redbuds in our yard do not seem to be affected. Is this a disease, a drought protection strategy or both?

ANSWER:

We're assuming that what you have is Cercis canadensis (eastern redbud), as that is the only one in our Native Plant Database that is found naturally in Virginia. Plants native to an area are much more likely to do well in that area, which is why the Lady Bird Johnson Wildflower Center is focused on promoting and preserving plants native to North America.

This Florida Cooperative Extension Service website on the redbud has a great deal of information about the culture of the Eastern redbud, as well as some of the common causes of problems. The only reference we found to black spots on the leaves was in reference to too much rain, so that's probably not your problem. The Eastern redbud can be both an understory tree or stand in full sun, but if you've had a dry, hot summer and the tree in question is in full sun, it may be stressed by that. If that's the case, hopefully some deep watering by sticking a hose down in the surrounding soil and turning on a slow drip for an hour or so will help.

So much for the weather being the problem. How about disease and/or critters? Borers can attack the trunks of older or stressed trees. To prevent this, keep the plant vigorous, which is what you're trying to do in the first place. Scale insects can infest the tree, and can cause sooty mold, which might explain the black spots on the leaves of your tree. Webworms may defoliate parts of the tree in summer and fall. The caterpillars are the larval form of the tiger moth, and they build ugly web nests in the spring or fall. Ugly as they are, they rarely cause any lasting damage. Probably the biggest problem in redbuds is canker. Bark in the canker turns black and a crack forms between diseased and healthy brk. The fungus enters through wounds or dead and dying branches. There is no chemical control, but spread can be at least slowed down by pruning out diseased branches. And, finally, verticillium will attack and kill Eastern redbud.

So, now that we've convinced you that your tree is a rooted Emergency Ward, let's just hope that cooler weather, more water, maybe at least some cloudy days for shade will begin to perk up the patient.

 


Cercis canadensis

 

 

More Trees Questions

Illegal to remove an orange blossom from ground in Florida from Atlantis FL
March 28, 2012 - Is there any law that prevents someone from removing an orange blossom from the ground in Florida?
view the full question and answer

Bugs on Arizona Cypress in Bellwood IL
August 27, 2011 - I live in Illinois and have an Arizona Cypress that looks like it is dying but I notice today it has bugs inside its cone. Can you tell me why and what can I do?
view the full question and answer

Need plants to replace cedars on a 40 degree slope in Boerne, TX.
August 28, 2012 - My backyard is a roughly 40 degree slope that is covered with cedars. The slope is basically all rock, what can I grow here to replace the cedar which drink too much water. I would still like the area...
view the full question and answer

Madrone too close to house in Oregon
February 02, 2009 - I have a small Madrone tree (8ft tall) located approximatly 15 feet from my house, with a basement. Should I remove it? ie will it damage the foundation and is the tree strong enough that it will no...
view the full question and answer

Native conifer bearing evergreen for noise reduction
April 01, 2008 - I asked the prior question about noise reduction and you gave me several choices. Thank you for that. Of the plants you suggested, the wax myrtle is the tallest and therefore probably best for my 2-st...
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 | STAFF
© 2015 Lady Bird Johnson Wildflower Center