En Español

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

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

Monday - May 20, 2013

From: Leander, TX
Region: Southwest
Topic: Plant Identification, Herbs/Forbs
Title: Identity of a yellow-flowered wildflower with prickly burs
Answered by: Nan Hampton


Hi there. We have seen a wildflower, probably invasive, that is at least in Travis, Williamson, and Hays counties. We have tried to identify it without success, The structure of the plant is remarkably similar to Malta Starthistle, but the yellow flower is daisy-like, not brushy like a thistle. The plant has horrific little burs with spikes, again like Malta Starthistle, but with shorter spikes. They are a serious enemy to barefoot people. They seem to like disturbed areas along roadsides in full sun. I never saw them five years ago when I bought my land north of Jonestown, and now they are everywhere. Any help would be appreciated.


For purposes of comparison, here is a link to Centaurea melitensis (Malta star-thistle), a native of Africa and Europe.

Here are a couple of possibilities for the plant you are seeing:

Solanum rostratum (Buffalobur nightshade) is a Central Texas native.  It has spines on its stems and spiny burs as seed cases.

Tribulus terrestris (Puncturevine) is native to southern Europe, southern Asia, Africa and Australia.  The spines are short and stout and can puncture bicycle tires! Here are photos and more information from Texas Invasives and University of California Integrated Pest Management.



From the Image Gallery

Buffalobur nightshade
Solanum rostratum

Buffalobur nightshade
Solanum rostratum

Buffalobur nightshade
Solanum rostratum

Buffalobur nightshade
Solanum rostratum

More Herbs/Forbs Questions

Low maintenance grass for shade in Conroe, TX
September 15, 2012 - What is the best low maintenance grass to plant in front lawn shaded, no traffic area?
view the full question and answer

Plants for north side from Dale TX
February 10, 2012 - What native trees and bushes can I plant on the north side of house? Can I use corn meal( I NEED FIGHT A GRASS) in flowerbed and then plant native wildlife seeds(FLOWERS)?
view the full question and answer

Fertilizer amounts for native perennials in Belton, TX
March 18, 2009 - I am a novice gardener and need advice on how to fertilize my native perennials. I would like to use organic fertilizer and need advice on exactly what to use. I have a compost pile but it does not ...
view the full question and answer

Plants for shade, poor soil in Park Ridge NJ
June 17, 2010 - Hello! I live in far northeast New Jersey, by the New York state border. I am looking for plants for areas of my lawn that nothing currently grows in - due to shade and poor soil quality - very rocky,...
view the full question and answer

Native plants to preserve soil on river bank
May 28, 2006 - I live in eastern Massachusetts. We have a small stream in our backyard and a woodland area on the other side. Japanese Knotweed is pretty well established on the opposite bank of the stream from our ...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center