Host an Event Volunteer Join Tickets

Support the plant database you love!

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

Sunday - October 16, 2005

From: Nashville, IN
Region: Midwest
Topic: Non-Natives
Title: Non-native, invasive, poisonous Chinese yam
Answered by: Nan Hampton and Joe Marcus

QUESTION:

I found a vine in my yard [central Indiana] which I believe is Dioscorea oppositiflora and I wanted first to confirm my identification and second to find out about edibility [especially of the airborne tubers] and uses. It has single and paired tiny potato like tubers in the leaf axils. the leaves are deeply veined and a deep lobed elongated heart shape. It is fall and I have not observed the inflorescence. Apparently there are several species [subspecies?] of Dioscorea? Thanks.

ANSWER:

Chinese yam or Cinnamon vine (Dioscorea oppositiflora, syn. D. batatas) is a non-native vine introduced from China into North America as an ornamental. Both the tubers and the bulbils (the tuber-like growths in the leaf axils) are edible if cooked. However, the Poisonous Plants of North Carolina database lists the uncooked tuber as toxic. Your description doesn't conflict with that of D. oppositiflora, but we can't absolutely identify a species by description alone. Certainly, we wouldn't want to try doing this if it is something you intend to eat. Note of caution: Get a positive identification of your plant before you eat it!

Although it is attractive, D. oppositifolia (along with two other members of the Genus Dioscorea, D. alata and D. bulbifera) is a fast growing and aggressive vine that is considered an invasive weed in the southeastern United States. For an extensive discussion of the biology, uses, invasiveness, and control measures for D. oppositifolia see this article from The Nature Conservancy.
 

More Non-Natives Questions

Non-native St. Augustine grass failing for 5 years in Houston
July 21, 2013 - My townhome in Houston has a mid-size backyard, which receives full sun for much of the day. I've re-sodded with St. Augustine for 5 consecutive summers, but it consistently dies over time (proper fe...
view the full question and answer

Alternatives to non-native, invasive Pampa grass
August 11, 2006 - Could you please tell me if Cortaderia Selloana is "zone 4" hardy? Also how to start Opuntia Humifusa from cuttings? Do I let them stand upright dry and with no soil until they form the callous? Ple...
view the full question and answer

Keeping non-native invasive bermudagrass out of yard in Austin
May 30, 2012 - My neighbor just sodded a huge lawn with Bermuda Celebration. I don't want it coming into my St. Augustine. From what I've read on your site and others, I need a deep barrier. Has anyone tried pu...
view the full question and answer

Non-native pittisporum disease in Austin
August 09, 2009 - Did Barbara Medford of Round Rock, TX ever find out what was causing sections of her dwarf pittosporum to die out? I have seen this in many yards now.
view the full question and answer

Why is non-native, invasive dandelion called a wildflower?
January 24, 2007 - Why is a dandelion a wildflower? {I read it in a book.}
view the full question and answer

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