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
1 rating

Wednesday - January 11, 2012

From: Florence, MA
Region: Northeast
Topic: General Botany, Herbs/Forbs, Trees
Title: Allelopathy in Sassafras albidum
Answered by: Jimmy Mills

QUESTION:

Sassafras albidum description says "Sassafras is allelopathic and can discourage the growth of certain other plants within its root zone." My question is: WHICH plants are susceptible? Or not susceptible?

ANSWER:

Sassafras Sassafras albidum (Sassafras) is a moderately fast growing, aromatic tree that is found in forest stands from southwestern Maine, south to northern Florida, and west as far as eastern Oklahoma and Texas. This description from “Silvics of North America, vol. 2 “ from the USDA has a very good chapter on Sassafras albidum, which addresses the question of allelopathy. It references the paper "The allelopathic influences of Sassafras albidum on old-field succession in Tennessee" Gant, R. E., and E. E. Clebsch. 1975. Ecology 56:604-615.  (click here to see abstract)

The following is a summary of the results of that study.

Vegetative surveys of 12 different stands of Sassafras albidum located in various study areas across the state were made. The vegetation was sampled to document which ground cover species occurred beneath and which were found outside the sassafras canopy. In general, more species were present and the percentage cover was higher outside the canopy.

Of the 37 species found in the survey, 17 were consistently higher in percent cover beneath or outside of the sassafras canopy. Ten of the 17 species that occurred outside  the canopy were as follows: 

annual herbs, Ambrosia artemisiifolia (Annual ragweed)and Cassia nictitans;

perennial grasses Andropogon virginicus (Broomsedge bluestem), and Tridens flavus var. flavus (Purpletop tridens);

biennial herbs Daucus carota, Rubus allegheniensis (Allegheny blackberry), and Rubus hispidus (Bristly dewberry);

perennial herbs Lespedeza striata, Plantago macrocarpa (Seashore plantain), and Solidago spp.

Seven perennials were more successful beneath the canopy; Asplenium platyneuron (Ebony spleenwort), Fragaria virginiana (Virginia strawberry), Lonicera japonica, Panicum virgatum (Switchgrass)., Parthenocissus quinquefolia (Virginia creeper), Paspalum setaceum (Thin paspalum), and Toxicodendron radicans ssp. radicans (Eastern poison ivy)  (also known as Rhus radicans).

Another part of the study tested the effect of some of the terpenoid compounds produced by sassafras on seed germination.  The following species  showed reduction in radicle growth in these tests.
Acer negundo (Ash-leaf maple), Acer saccharum (Sugar maple), Albizia julibrissin, Pinus virginiana (Virginia pine), Sorghum halepense, and Ulmus americana (American elm).




 

From the Image Gallery


Sassafras
Sassafras albidum

More General Botany Questions

Withering plants recover with water
February 17, 2008 - Why do withering plants stand up when you give them water?
view the full question and answer

Classes for a nature lover in Frisco TX
August 16, 2009 - I have a question which I don't think is available in this website. I love plants & flowers,trees etc- just like you, I've only studied till my higher secondary school; now would love to study as we...
view the full question and answer

Effect of epsom salts and gray water on plants
December 04, 2007 - We live in Phoenix where water is a precious commodity. We have decided to use as much of the gray water as we can for watering our garden, shrubs and trees. One of the suggestions we heard about w...
view the full question and answer

Manzanita struggling in CA
March 01, 2012 - I live in Monterey, CA and I have had a manzanita (either Dr. Hurd or Mt. Hood) growing successfully in my yard for about 4 years. This fall all the leaves turned brown and brittle. I am not sure if d...
view the full question and answer

Starting a sweet potato in water in Duluth MN
April 11, 2011 - I am trying to start a sweet potato plant in water. I noticed 3 days after it's in water, there is white finger like(hairy) areas at the tip of the bottom of the potato and also on the sides. I have...
view the full question and answer

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