Growing in drainage line with originally close to 1000 reduced over several years to less than 100 plants, and after last Sunday 18 August 2019 work party hopefully to less than 10. There is constant water flow from a leaking water tank; the drain line sits on top of a tributary to Sullivans creek.
Unfortunately, there are other sites in the reserve where Cyperus eragrostis grows. They are along drain lines that had been artificially widened/made/enhanced. I started control at this particular site to reduce seed spread into the Sullivans system (several years ago I observed C. eragrostis being sprayed close to the Dickson oval).