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
1 rating

Friday - March 23, 2012

From: Fort Worth, TX
Region: Southwest
Topic: Invasive Plants, Non-Natives, Plant Identification
Title: Identity of the mass fields of yellow flowers in North Texas
Answered by: Nan Hampton


Are the mass fields of yellow flowers we are seeing in north Texas now likely to be Indian Mustard (brassica juncea) or Charlock (brassica kaber or sinapis arvensis)? We are teaching a wildflower idenification class at a community college and are ourselves confused about this identification. Thanks for the help.


The mass fields of yellow flowers we are seeing around Austin are the invasive non-native Rapistrum rugosum (Bastard cabbage).  See the USDA distribution map (if you click on the map, it will give you an enlarged map with county names).

Brassica juncea (Indian or brown mustard) (see the USDA distribution map) and Sinapis arvensis [syn. Brassica kaber](charlock mustard) (see the USDA distribution map) are certainly possibilities, however, around your area near Fort Worth.

Here are photos for Brassica juncea from Stephen F. Austin University, photos of Sinapis arvensis in FlowersInIsrael.com and photos of Rapistrum rugosum from Biological Sciences, University of Texas.

Here are the descriptions for the three species in Flora of North America as seen on eFloras.org:

Brassica juncea

Rapistrum rugosum

Sinapis arvensis

You can also find descriptions of the three species in "Shinners and Mahler's Illuststrated Flora of North Central Texas" on pp. 459, 476 and 479.

If the photos and descriptions don't help you determine which of these you are seeing, you might consider contacting someone knowledgeable about the flora of your area—for instance, a member of the North Central Chapter of the Native Plant Society of Texas (NPSOT)—to see if they know the identity of these flowers.


More Non-Natives Questions

Difficulty with Clay Soil from Palm Bay, FL
August 22, 2012 - I had a very nice little native shady area behind my house for over 40 years, but now it has been cleared except for a 100 foot tall live oak in the center of this raised mound (50' x 80'). I've be...
view the full question and answer

Is my Crimson queen maple dying?
October 20, 2015 - Is my Crimson queen maple dying if it's leaves are turning brown?
view the full question and answer

Native plants of Rome
February 22, 2009 - I am researching the native plants of Rome but I can't get anything get anything else besides olives. Can you help me to find some more?
view the full question and answer

Problem with non-native gerbera daisies
June 09, 2009 - My gerber daiseys leaf but they don't want to bloom. They come back. What am I doing wrong?
view the full question and answer

Non-native, invasive creeping fig in Webster TX
May 26, 2013 - We've recently moved into a new home in the southeast Houston area. The back of our property has a long concrete wall (gets quite a bit of sun), which we thought we could cover with a spreading vine....
view the full question and answer

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