There are several variations of the weeds known as leaf flower or mimosa weed including chamberbitter and niruri. They are not easy to control. Handpulling is difficult since the weeds occur in large numbers and tend to break off at the ground. Mulching flower beds will keep the seeds from being able to germinate if a 3" mulch is maintained, especially during the warm season when these weeds begin to germinate. In flower beds a postemergent weed killer containing glyphosate (Roundup is one example) or glufosinate (Finale) can control the weeds after they emerge. These products however can kill desirable plants too so care must be taken to not allow the spray to get onto foliage of desirable plants. In turfgrass a postemergent 3-way herbicides containing dicamba, 2,4-D, mecoprop (MCPP) (such as Trimec Southern or Weed-B-Gon for Southern Lawns) can be effective in controlling the weeds after they emerge. A second application about a week later may be needed. However these products used when temperatures are in the upper 80's and above can damage or stress the turfgrass. Since the weed tends to germinate with the arrival of warm weather this may make their use questionable, especially on St. Augustine lawns. In future years the use of a pre-emergent herbicide containing isoxaben (such as Gallery or Snapshot) applied in March and again in early June can help prevent germination.
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