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An analysis of the decision rules and the variable effects when applied to Overseer as a tool to predict N loses from s given set of inputs and management strategies resulting in specific production outcomes.


Example of a GSL Farm Report showing the the data input and the analysis output plus discussion. Analysis


‘Benchmarking’ and the term “comparative analysis” are often used to describe a process that is more akin to “reading the tea leaves” than objective analysis.


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Our Mission

GSL’s mission is to introduce farmers, farm advisors, farm service providers, regional authorities, government organisations plus politicians to the concept of readily applicable marginal production analysis for the betterment of NZ’s pastoral farming production system.

Our primary objective being an improvement to an individual farmer’s profitability by the best use of the farm businesses physical and financial resources through the delivery of a systems management strategy best fitted to an individual farms factors of production.

Our secondary objective is environmental improvement through the least cost steps for reversing environmental degradation as a result of production intensification, by showing where marginal non-profit contributing intensification practises are contributing to environmental damage at an invisible cost to the producer, the processor and the community.


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Our Recent Work

GSL Analytic Process

GSL has produced software that is able to analyse the complex relationships of profitable livestock production system. GSL software produces actionable management plans to maximise profitability from available farm resources.

Sheep Beef & Mixed Farming

Need to know the best combination of sheep, beef, cash cropping and contract grazing? Or, in times of low dairy payouts, at what point is bull beef production more profitable than milk production taking into account the sunk capital investment in dairy production?

Production Economics Simplified

The simple question to be asked when making any investment is whether the future return is worth the price being paid today. This implies that not all benefit may be of a monetary nature, but if a business is to survive, the luxury of not making profit at some time is not a sustainable option.

Integrated Resource allocation

It is known as linear programming (LP) but actually the GSL model allows use of nonlinear as well as linear data necessary to establish the optimal production level for any mix of resources in a biological production system.

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What We Do

  • Objective: To provide analysis of individual farms showing the best mix of farm resources to be applied for an optimal production systems strategy.

    Outcome: A report listing a range of farming scenarios showing outcomes resulting from the utilisation of the base farm resources with the application of selected input and output constraints but solving for a targeted objective function be it maximum profit, minimum N excreted or maximum physical production.
  • Objective: To change farm management thinking from input/output (accountancy/finance) driven models to optimisation models (of all resources) where the new concept shows the maximum production obtainable utilising all resources (physical and financial) for maximum profit or any other objective that can be quantified such as minimum N leach.

    Outcome: An optimisation model introduces the concept of MC
  • Potential Users and Beneficiaries of Farm Systems Modelling

    1. Farm businesses seeking profit improvement.
    2. Farming industry decision makers
    3. Regional authorities managing environmental issues
    4. Government Ministries managing the nations resources

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What “A new way of thinking” means to GSL’s customers

  • GSL enables a new way of thinking for my clients, we are able to explore alternative options and find the best fit for their farm.
    Farm, Consultant
  • GSL has allowed me to think about the farm in new ways, I am no longer hesitant to try new farming methods, as GSL reduces the risk
    Farm, Manager
  • The GSL system is a new way of thinking about my farm. I used to see it as segmented parts but this allows me to view it as a complete business unit.
    Farm, Owner
  • The GSL system is a new way of thinking for farmers, they no longer stick with the status quo, and they are able to explore the most profitable options for their land.
    Farm, Accountant