Got Buttercups and your not sure whether to use Rainbow & Brown Decision (flumetsulam) or Ranger (thifensulfuron-methyl) then read on.  Prices below were effective February 2020.

DECISION

Boom spray at around 50g/ha for Creeping buttercup and 65g/ha for Giant Buttercup.

So that is only $19.50/ha to spray for Creeping buttercup and a heap of other weeds.

Plus Decision controls a number of other weeds that might be present as well including chickweed, cleavers, mallow, oxeye, sorrel, spurrey, stinking mayweed, willow weed, and many other weeds.

Decision  is pasture and clover friendly but it is not really effective against docks so if you have docks as well as buttercup check out Ranger below.

RANGER

Boom spray at around 20g/ha.  Great for Docks and Buttercups.

So that is only $11.96/ha to spray for Buttercups and/or docks

Ranger is slower to act than Decision and can cause some a slight reduction in pasture vigour and knocks back clover but it is a really cost effective solution.

So in summary if you have mainly docks and buttercup then Ranger is a cheap herbicide to use.  If you don't have docks but have a few of the other weeds, you need quicker results or you have reasonably new pasture, then Decision is the way to go.