Bruce from Brooksville, Florida writes
The label says for use on St Augustine grass but does not list the varieties that are approved.
Floratam is not listed on the Poa Constrictor label as having been tested for tolerance (only Raleigh St. Augustine is specified). Since Floratam is notoriously sensitive, and the product label does specify that the herbicide may cause discoloration on St. Augustine turfgrass, we recommend testing an inconspicuous area for tolerance before treating the entire lawn.
Answer last updated on: 10/01/2019
