Best Management Practices:
Prostrate knotweed is a warm season, annual broadleaf weed that has prostrate, mat-forming, branched stems. Its leaves are smooth, alternate, and somewhat blue-green in color. These linear/oblong leaves join to the stems by a sheathing membrane and its dull brown seeds stay viable for many years. Its presence is usually considered a sign for compacted soils as well.
Prostate knotweed begins its life by germinating in the early spring from seed. Pre-emergent herbicides work by killing germinating seeds from weedy plants like prostrate knotweed. Normally, an application of a pre-emergent like XL- 2G (Benefin plus Oryzalin), Pendulum 2G or Anderson 11-3-11 (Pendimethalin) or Balan 2.5 G in late February will work well. Remember, though, that this weed may germinate into the summer—so, a second pre-emergent application in the month of May is recomended.
If your weeds escape 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 prostrate knotweed is very young/immature and actively growing. Do not wait until late summer when these annual broadleaf weeds are flowering and mature. Examples of an effective product to be used are: Speedzone, Crab-E-Rad Plus, Weed Free Zone and Trimec Southern. CAUTION: Make sure you read the labels carefully for the tolerance level of your specific turfgrass for all herbicides.
Best Management Practices courtesy of:
Bes-Tex Supply, LLC P.O. Box 664 San Angelo, Texas 76902 Ph. 325-653-1300