Hamilton EverGraze Proof Site: Report on the impact of changing management regimes on profitability

The experiment at the Hamilton Proof site at PVI was conducted by EverGraze between 2006 and 2010. The ‘Standard’ livestock enterprise run at the site was a Merino ewe joined to a Terminal ram. The second system run at the site was a Composite ewe joined to Terminal ram. In addition, the two livestock systems were both run on the following two pasture systems (i) Perennial ryegrass system – PRG – (three cultivars of ryegrass in different parts of the landscape – Fitzroy, Avalon, and Banquet) or (ii) Triple System (three species in different parts of the landscape – Sardi 7 lucerne, Avalon PRG and Quantum tall fescue). For these four systems, several simulations using GrassGro version 3.1.3 were conducted to evaluate the impact of changing prices, different seasonal conditions, and changing management (allocation of green feed in summer, lambing time, stocking rate). Three alternative livestock systems were also evaluated. They were a self-replacing Merino flock, a self-replacing composite ewe enterprise and a self-replacing beef herd.