En Español

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?


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
1 rating

Wednesday - January 11, 2012

From: San Antonio, TX
Region: Southwest
Topic: Diseases and Disorders, Drought Tolerant, Trees
Title: Leaves dropping on evergreen sumac in San Antonio
Answered by: Barbara Medford


I have a large evergreen sumac in my back yard that started off as a small shrub 10 years ago. This summer the leaves turned red and now have dropped off. Is the plant dead? It sent out two smaller plants which look fine so far, but I don't want to lose them either. Local plant experts can't figure out what may have happened, since I have done nothing different to the plant or my yard in the entire time I have lived here.


Rhus virens (Evergreen sumac) is, according to this USDA Plant Profile map, native in the area of Bexar County. It is not a true evergreen; like live oaks it drops its leaves in the Spring, which are quickly replaced by new leaves. The two small plants that you are seeing are actually shoots, still part of the original tree, and emerging from the same root. We are guessing, although this tree is drought tolerant, that our unusually hot and dry weather caused it to be drought-deciduous, dropping its leaves early to protect the roots.

You aready know, because of the shoots, that the roots are still alive. Use the thumbnail test to see if any of the stems have died. Beginnning fairly close to the top (or as high as you can reach) scrape off a very thin layer of the bark with your thumbnail. If there is a thin layer of green beneath the bark scraping, that trunk is still alive. You can check other areas or branches and, if you find no green layer, move farther down on the same branch.

We could find no projected age for this plant, but its mature height is usually about 8 to 10 feet. We did find information saying it could tolerate extra watering if it was in a well-drained soil but since, as you say, the care for it has not changed in 10 years, we doubt that could be the problem. At this point, we prescribe patience. If you found the green underskin, it is probably just waiting for better times. Leaves should begin to reappear in the Spring, per schedule.


From the Image Gallery

Evergreen sumac
Rhus virens

Evergreen sumac
Rhus virens

Evergreen sumac
Rhus virens

More Diseases and Disorders Questions

Juniper-apple rust galls
April 24, 2010 - I have Red Cedar trees in my yard. I have just noticed something that looks like a reddish brown squid-like bloom about the size of a small orange. Is this normal or is it a fungus?
view the full question and answer

Beneficial earthworms attacked by fire ants
August 04, 2006 - Is there a right way or a trick to releasing earthworms? I have a friend who has an abundance of earthworms in their soil so I took advantage of the situation. I released them in my freshly tilled gar...
view the full question and answer

Bark splitting in old tulip tree in Red Creek, NY.
May 18, 2013 - Hello, We have a tulip tree that has some bark splitting I guess I would call it. The tree is older and very tall. On the north side of it starting at the bottom of the trunk to about 8-9 feet up i...
view the full question and answer

Esperanza freezing back in Highlands, TX
April 16, 2011 - I have an 3 yr. old Esperanza that froze the last two yrs. but grew back each spring. This spring after getting about 2 ft. the leaves at the bottom began turning brown at the edges and now seems to...
view the full question and answer

Insect pests in Gaillardia aristata in Tennessee
August 22, 2008 - Dear Mr. Smarty Plants, I have a couple of 'Oranges and Lemons' blanketflower plants in a butterfly and hummingbird native flower garden that is the foundation planting of my house. They bloom prol...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center