A major update to the way OverseerFM models crops has been welcomed by the arable industry.
The upgrade removes the seasonal variations of crops to describe and estimate the impact of how crops are farmed more appropriately.
“In the past many crops have been an assumption rather than actual data. The cropping industry certainly welcomes the new capabilities and applauds the work of Overseer and Plant and Food specialists in achieving this result,” Federated Farmers arable chair Colin Hurst said.
“For crops, in the past we have had to put in a proxy. This improved software addresses that problem.”
Hurst said the new way of modelling crops will enable a better representation of what is happening in a farm system.
“I know here I have up to 12 different crops in the system at any one time and they all have individual inputs, it’s a lot of data to input,
“I understand the new software modelling makes it easier for growers to input information. Anything that improves the accuracy and the use of the software is good news for farmers.”
The comprehensive farm nutrient management tool has improved the software’s crop modelling capabilities with extensive crop changes incorporating new information from cropping specialists at Plant and Food Research.
The update includes the addition of new crops and considers the crop rooting system.
“In a deep rooting system we know roots go down a lot more than 60cm, it is what they do – are they getting water or harvesting nutrients?
“If there are nutrients in the top 60cm they will naturally take those up first, if no nutrients in the top 60cm they will start taking up nutrients.
“This has been accounted for in the updates,” OverseerFM business development manager Alastair Taylor said.
“Previously, one of the issues was that the growth of a crop was fixed in the model with the growth time set at a national average value.
“If you grew a crop for only three months when the national value was six months, the model would go through a six-month process, which would limit the accuracy of the model.
“Under the new model, crops now have a farm-specific growth curve and are more representative of what is actually happening in the farm system,” Taylor said.
Users can now also specify product loss occurring in the field.
As an example, a broccoli crop might have 5-10% of spoiled heads left in the paddock. These have grown and taken up nutrients.
The model can now allow for field loss of damaged crops, which will be incorporated into the results.
The update has also added four new crops – chickpea grain, pak choi, rape green manure and turnip green manure – and allows for further additional crops to be more easily added.
An issue around the modelling of fodder beet has been resolved and modelling has been reviewed for crops of broad beans, green beans, cauliflower (winter/spring), cabbage (winter spring), spinach, oats and rye, broccoli (summer), turnips (leafy) cabbage (summer) and radish.
Overseer Limited and independent scientists have been assessing the tool’s reliability in a range of areas including deep-rooted plants, the effects of different climate data sets, multi-layer soil and sensitivity and uncertainty.
The work to update the crop model began in 2020 with Overseer Limited working with Plant & Food Research.
The first outcomes of that programme, updating crop parameters for some existing crops and significantly extending the number of crops that could be modelled, were added to OverseerFM in late 2021.
“We knew there were some quick gains to be made in adding new crops and some cropping changes.
“We then went on to do the longer-term work, with support from the Ministry for Primary Industries.”
The work considered the findings of an independent science review of the OverseerFM model, released in August 2021.
“It has taken time, as it was complex work and difficult to incorporate into the model. However, as a result we now have something better for farmers and growers.
“Farmers may notice their numbers change but the main difference will be that the way crops are modelled should be more representative of what is actually happening in the farming system.”
The updates also mean it is now much easier to collect data for incorporating new crops into the model.
The changes do not include any update to how pasture or pasture crops are modelled.
