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

Saturday - March 30, 2013

From: Clarkridge, AR
Region: Southeast
Topic: Non-Natives, Edible Plants, Trees
Title: Will corn fall victim to allelopathy from hackberry in Clarkridge AR
Answered by: Barbara Medford

QUESTION:

Will my corn be inhibited by a nearby hackberry and if so would it help to cut it down? I understand that sometimes the soil is full of the chemicals the tree produces.

ANSWER:

What you are probably referring to is allelopathy, which is the production of chemicals in some plants that inhibit growth in competing plants nearby. This article from Cornell University includes this statement:

"One of the most famous allelopathic plants is Black Walnut (Juglans nigra).  The chemical responsible for the toxicity in Black Walnut is Juglone (5 hydroxy-1,4 napthoquinone) and is a respiration inhibitor.  Solanaceous plants, such as tomato, pepper, and eggplant, are especially susceptible to Juglone.  These plants, when exposed to the allelotoxin, exhibit symptoms such as wilting, chlorosis (foliar yellowing), and eventually death.  Other plants may also exhibit varying degrees of susceptibility and some have no noticeable effects at all.  Some plants that have been observed to be tolerant of Juglone include lima bean, beets, carrot, corn, cherry, black raspberry, catalpa, Virginia creeper, violets, and many others."

Black walnut isn't the only tree that produces juglone. This chemical is also secreted in smaller amounts by English walnut, hickory and pecan trees.Other trees with allelopathic properties include tree-of-heaven, sugar maple, hackberry, American sycamore, American elm, southern wax myrtle, cottonwood, black cherry, sassafras, red oak and black locust.

So, we know about Black Walnut not being a threat to your corn, now to find out if Celtis laevigata (Sugar hackberry), which is a member of the Ulmaceae (elm) family, could exibit allelopathy. We found this list of pests in corn:

Frankly, we think any of them would be worse than a nearby hackberry. Since the center of origin of  Zea mays (corn) is believed to be native to Mexico or Central America, we don't know  too much about it. If your (native) hackberry is shading the corn, you might want to think about it, but otherwise, we feel the corn is safe.

 

From the Image Gallery


Sugar hackberry
Celtis laevigata

More Trees Questions

Arborvitae for house plant from Austin
August 15, 2013 - I am a Northerner transplanted to Austin, TX. While I love Austin it feels like many of the plants & trees I came to love up north won't grow here at all. Could I grow an arborvitae in my home as a...
view the full question and answer

Will Texas madrone (Arbutus xalapensis) grow in northeast Texas?
November 24, 2009 - Will Texas madrones grow by Cedar Creek Lake and if so, do you know where I could purchase them "sort of" locally?
view the full question and answer

Powdery Mildew on Monterrey Oak
July 30, 2015 - Monterrey oak developing gray-white patches on some but not all leaves leading to wilting. could this be powdery mildew? Tree not stressed. Thanks. Best treatment?
view the full question and answer

Mimosa shape
November 27, 2007 - I planted a summer chocolate mimosa, and although it has bloomed lovely foliage, it has two main branches growing in a vee shape. Is this normal? Do I need to do anything to spur the growth in a more ...
view the full question and answer

Leaves on Spanish oaks in Hays County TX dying
April 18, 2009 - I have many Spanish Oaks on my Hays County property. The leaves started blooming last week, but this week all the young leaves are brown and appear to be dying. This is happening to all the otherwise ...
view the full question and answer

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