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?


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
2 ratings

Sunday - April 25, 2010

From: Myrtle Beach, SC
Region: Southeast
Topic: Non-Natives
Title: Ridding non-native centipede grass of native rattlesnake weed in Myrtle Beach SC
Answered by: Barbara Medford


How do I get rid of "rattlesnake weed" in my lawn of centipede grass in Myrtle Beach SC?


This puts us in a slightly embarrassing position. The Lady Bird Johnson Wildflower Center is dedicated to the use, protection and propagation of plants native not only to North America but to the area in which it is being grown. Your "weed," Hieracium venosum (rattlesnakeweed) is native to South Carolina, while your lawn, Ischaemum muticum, Centipede Grass, is native to China and parts of southeast Asia. Turns out both plants are considered by some to be invasive in nature. One source said that centipede grass can become a weed in many annual and perennial crops and can develop into huge thickets in drainage canals and ditches. 

However, to you the rattlesnake weed is the invasive. We have no personal experience with it (but we do with rattlesnakes!) but from the information we have it looks pretty hard to pull out, which is always our first choice in getting rid of something like that. Preventing it from blooming, so it cannot set more seed, is the first line of defense. As those blooms stand up pretty high off the ground, getting them mowed early will certainly help. 

Much as we hate to prescribe herbicides, because of environmental reasons, that may be your last resort. Centipede grass is a monocot, like all grasses. Rattlesnake weed is a dicot, also classified as a broad-leaf plant. You can buy herbicides specifically for either; obviously, you want one for a dicot, or broad-leaf plant. Read the instructions carefully, and follow them closely. Broadcast spraying could, with a gust of wind, damage some shrubs, flowering plants or trees, because they are dicots, also. 

Conclusion: Prevent the Hieracium venosum (rattlesnakeweed) from seeding if you can, pull it out of the ground when it's possible, use a dicot herbicide as a last resort. But mind the rattlesnakes!

From our Native Plant Image Gallery:

Hieracium venosum

Hieracium venosum

Hieracium venosum




More Non-Natives Questions

Non-native Merremia tuberosa
August 07, 2006 - Respected Sir, I have been trying to find the scientific name and a sapling of a plant which had "flowers that look like rose flowers but are brown in color and have a paper like...
view the full question and answer

Failure to bloom of non-native viburnum in Dayton, Ohio
April 30, 2009 - I have a 3 year old Marie's Doublefire Viburnum that has healthy, abundant foliage but never blooms. I do not prune it. What am I doing wrong? Thanks
view the full question and answer

Damage to plants after sudden freeze in Redway CA
January 02, 2010 - I live on the North Coast of California near "The Avenue of the Giants" and Redwoods State Park along the Eel River. We recently have had below freezing weather, constant rain and even snow! I have...
view the full question and answer

Problems with non-native navel orange
October 03, 2008 - Hello Green Guru, Question: Why hasn't Navel Orange Tree grown or sprouted new branches? It's 3 years old and is about 5 feet tall and has remained this size. It hasn't grown at all. It only ha...
view the full question and answer

Replacing St. Augustine grass from Dallas TX
April 10, 2014 - Dear Mr. Pants, we are replacing dying St. Augustine grass in a small, sunny back yard with ground cover. What are your recommendations for a drought-tolerant evergreen ground cover? We will till a...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center