By Jake Landers
Published July 2012
Buffalo Burr (Solanum rostratum) is a member of the Potato Family, many of which are poisonous to humans and grazing animals. Our familiar Irish Potato occasionally is green in the outer layer of the tuber that contains solanine, a poison thought to cause spina-bifida in babies when overconsumed by pregnant women in Britain.
There are no tubers or other food storage roots in Buffalo Burr. It must grow each time from seed which can last many years in the soil. Perhaps soil disturbance, as in a Buffalo wallow, brings seeds to the surface where they can germinate. Another name is Kansas thistle.
Burrs clinging to the shaggy hair of the beast could have assured transport throughout the plains where Bison roamed in earlier times. Too bad the Bison couldn’t have benefited from a little good grazing in exchange for spreading the plant around.
Although it’s a native plant with attractive yellow flowers on our plains and prairies, most thoughtful outdoor people would consider it a weed. It may be unusual to find it in a lawn as shown in the accompanying photos. It came up where I had filled in my lawn with some soil from the ranch, where it can be abundant in overgrazed pastures, garden, water lots, and bedding grounds. I have seen it many times on ranches in our area, but I remember no situation where there was a major effort to control it. Usually it took care of itself the next growing season.
The leaf pattern and the abundance of stickers give a positive identification of Buffalo Burr at a glance and feel. Close examination of the flower structure, usually depended on for identification of most plants, would reveal snout-like anthers releasing pollen that somehow gets distributed to another flower by a pollinating insect.
Reading The Landscape
Here’s a plant that was very abundant this spring in central Texas and elsewhere—probably in every field, roadside and pasture. What is it? What are the conditions under which you would expect to see it again? Click here for Jake's answer.
Jake’s summary: This 6-foot specimen of Scotch Thistle, Onopordum acanthium, a weed from Europe, thrives in May in a borrow ditch along a private road near Menard, Texas. Plants 12 feet tall have been reported. Seeds from the rather attractive flower heads are carried by the wind like Dandelions, and establishment begins as a rosette on open ground with abundant fall and winter moisture. Leaves are big, spiny, and gray-green, with ribbons of tissue up and down the stem. Plants mature and die in their first summer. I don’t know how to get rid of it. —JL