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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

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