OVERSEER® Nutrient budgets can assist with the following: Calculates on-farm budgets for a wide range of nutrients and farming systems (pastoral, arable/vegetable and fruit crops) based on data inputs readily available from the farm. Understanding the fate of these nutrients is an important precursor to developing a Nutrient Management Plan. Calculates and reports farm-level emissions (greenhouse gases) for farms based on the farm-specific methods that are related to the National Inventory methodology. Emissions are reported on a per hectare and per product basis. This allows users to identify major sources on farms and to test management strategies for decreasing emissions. Calculates maintenance nutrient applications for pastoral farms, i.e. the levels of nutrients required to maintain the current soil test values. Is a useful fertiliser planning tool on its own, additional software is used by fertiliser companies to provide farm specific econometric information for further developing fertiliser recommendations. This information can support farmers and their advisors in planning nutrient use and assessing the potential environmental losses. Can support environmental policy development, most notably around Lake Taupo and as a part of Horizons One Plan. OVERSEER® does not include economic analysis, so outputs needs to be combined with other economic models to assess impacts of options on the farm business.


OVERSEER® is an agricultural management tool which assists farmers and their advisers to examine nutrient use and movements within a farm to optimise production and environmental outcomes. The computer model calculates and estimates the nutrient flows in a productive farming system and identifies risk for environmental impacts through nutrient loss, including run off and leaching, and greenhouse gas emissions.

Latest Version 5.4.10
State of Development Released and updated
Current Development Activity V6.0 scheduled for release 3rd August 2012

Development Contact

Mark Shepherd
+64 7 838 5136
AgResearch - Ruakura Research Centre
East Street Private Bag 3115 Hamilton 3240, New Zealand

Main Developers

  • AgResearch
  • FertResearch


Outcome Areas Environmental
Management Domains Land, Freshwater
Subdomains Contaminant Losses, Crop/Farm Systems
Intended End Users Fertiliser representatives, farmers, scientists, policy researchers
Spatial Resolutions Unknown
Spatial Extents Land or Business Unit
Spatial Dimensions 1D
Temporal Resolutions Years
Temporal Extents Unknown
Steady State or Dynamic Steady State
Level of Integration Environmental

Input & Output Data

Key Input Data Land Use, Rainfall
Input Data Formats XLS(X)
Key Output Data Drainage nutrient loss


Open/Closed Source Closed Source
Licence Type No Licence

User Information

Operating Systems MS Windows
Software Needed Unknown
User Interface Graphical desktop
Ease of Use Easy
Use in Policy Process Plan (Policy Formulation), Do (Policy Implementation), Check (Policy Evaluation)

For Manuals, release notes, guides and technical manuals see:

Support Training courses available

Technical Considerations

Analytical Techniques Input/output
Keywords fertiliser, nutrient budgeting, nutrient management planning, greenhouse gas
Linkages to other Models
Key References


Associated Case Studies