the label for Surge is odd in that it suggests no application in spring or fall--as if cool weather would cause some problem. However Lesco Red Zone is a similar product. It lists Buffalograss as tolerant, and I see no such precaution on their label. It is actually similar to Speedzone. Which is similar to Trimec plus carfentrazone.
The product "Dismiss" which lists buffalograss, contains sulfatrazone one of the ingredients in Surge and seems to have no such precautions either.
Confusing. Why not try it on a small area--at the low rate--and the high rate. See if the results are acceptable. We would all like to know.