NORMAN — Have you ever stepped on a sandbur with bare feet? Isn’t that a lovely feeling; about like crawling up into your mother’s arms. I just love sandbur as I think it is a remarkable summer grass capable of growing just about anywhere. I hope by now you can sense my sarcasm. I talk to one or more people weekly with moderate to severe sandbur infestations on their small acreage, farms or ranches. While I sometimes grow weary talking about them, I never tire of telling people how to kill or prevent this menace to bare feet everywhere.
A perfect storm of events prefaced an absolute explosion of sandbur on the Oklahoma landscape in 2013; including several years of drought and overgrazing. These two things among others created weak competition and subsequently plenty of bare ground and allowed sandbur to run absolutely wild once the skies opened up and wet the central and eastern Oklahoma whistles.
Several species of sandbur infest the Southern United States, including field, longspine, and southern. While they are each different, they share the common trait of being loathed equally among both humans and pets alike.
All these varieties can be controlled by the same treatment method as they generally behave as summer annuals. They can grow 2 feet and the leaves are smooth, twisted and 3 to 5 inches. As the name implies, sandbur enjoys well-drained, sandy, somewhat deficient soils, but can grow just about anywhere and in any soil. Plants reproduce from seeds, which are contained in a bur with hard, sharp spines. Burs overwinter on or near the soil surface and can remain dormant in the soil for years.
Enough about the botany of this wretched plant; how do we get rid of it?
Some success in sandbur suppression can be achieved through cultural practices such as prescribed fire. Burning can sometimes reduce sandbur numbers, but is dependent on the timing and intensity of the fire and many other factors. The burn may stimulate more seed to germinate due to reduced cover and this allows landowners to kill more of the potential sandbur since more seed will emerge at once. Improving the density and height of bermudagrass through aggressive fertilization (according to a soil test) can also reduce sandbur numbers by crop competition. However, fertilization and burning should be thought of only as suppression methods and not as control. Sandbur suppression can also be achieved by not overgrazing and leaving 5 to 7 inches of bermudagrass stubble year round. Anything that minimizes bare soil will suppress sandbur.