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Field Sandbur (Grassbur)

Best Management Practices:

Field Sandbur ( Grassbur )

Field sandbur, also known as “grassbur”, is a warm season, annual grassy weed that normally has "reddish" stems at the base of the plant, sandpapery but smooth leaves, and a spiny bur in its seed head.  Being a warm season, annual plant means that it only comes back from seed each year, usually germinating in the mid/late spring season.  Grassbur also creates havoc in lawns because it will germinate seeds throughout the summer as well. 

Pre-emergent herbicides work by killing germinating seeds from weedy plants like grassbur.  Timing of application is critical so as to have a herbicide barrier in place at germination.  Normally, an application of a pre-emergent in late February or early March will work well.  Remember, though, that this weed may germinate into the summer—so, a second pre-emergent application in early May is warranted.

There are several pre-emergent herbicides that can be used to control grassbur in most turfgrass sites including bermudagrass, St. Augustinegrass, zoysiagrass, and buffalograss.  Examples include:  XL- 2G (Benefin plus Oryzalin), Pendulum 2G or Anderson 11-3-11 (Pendimethalin) and Balan 2.5 G .   

If you have grassbur that escapes the pre-emergent or you do not apply a pre-emergent, you may need to apply a post-emergent herbicide.  These herbicides can be effective if used when the grassbur is very young/immature and actively growing.  Examples of effective products are Image, and . They work very well together if used in the correct manner.  It may require multiple applications to obtain excellent control with these post-emergent products.  CAUTION:  MSMA can only be used on bermudagrass and zoysiagrass turf sites---NOT ST. AUGUSTINEGRASS!  Image, on the other hand, can be used on St. Augustinegrass, but may not perform as well as MSMA.  So make sure there is no wind to avoid drift and set your sprayer to where the droplet size is much larger (not a fine mist).

Best Management Practices courtesy of:

Bes-Tex Supply, LLC P.O. Box 664 San Angelo, Texas 76902 Ph. 325-653-1300