The data behind these graphs was evolved by Barrie Ridler in developing resource optimisation models of regional average NZ dairy farms. New Zealand Dairy Farms - Optimising Resource Allocation [1]

Interpreting these graphs is left up to the viewer. Reference to the above link will suggest links between farm profitability and location at higher lattitudes. Points for reflection include:

1. The effect of lattitude on the production of pastures based on temperate grass species - higher lattitudes presumably providing longer summer days at lower average temperatures
2. Comparisons of the lattitudes of worlds traditional and newer dairy production regions: New Zealand (36-46 S); Tasmania (42 S); UK/Eireland dairying (50-55 N); France (45-50 N); Wisconson (42-47 N); Mongolia (42-47 N)
3. The considerable variations in match between pasture production and milk production
4. The likely impacts of of early calving on the mismatch between pasture production and milk production
5. The wisdom of attempting to migrate NZ production systems to regions with latitudes lower than traditional pasture based dairy production. Uruguay for instance has lattitudes from 30-35 degrees South - lower than even Northland.

Northland Pasture Profile (lattitude around 36 degrees South)

Northland: matching pasture and milk production profiles

Waikato Pasture Profile (lattitude around 37-39 degrees South)

Waikato: matching pasture and milk production profiles

Lower North Island Pasture Profile (lattitude around 40-41 degrees South)

Lower North Island: matching pasture and milk production profiles

Southland Pasture Profile (lattitude around 46 degrees South)

Southland: matching pasture and milk production profiles