Biological Monitor Weather is a data point. What it does to your pasture is something else.
The IdeasFarm Biological Monitor is a model that tracks each paddock day by day and estimates how much pasture there is, what quality it has and whether it is short of water.
Follow a paddock for 33 days
Move the slider or play the cycle. The blue marks show each day's rainfall; the reading tells you what that weather meant for the pasture.
Weather for the day: 18 °C and 8 mm of rain
It rained 8 mm. Part of that rain replaced the water the crop had used and improved its water status.
44,6 % fiber
Illustrative simulation of a mixed-sward regrowth. The values do not correspond to a real farm.
Where the data comes from
Five sources, from space to soil. None is enough on its own.
The satellite is a variable, not the answer
NDVI measures how green the vegetation looks from space. On its own, it does not know which crop is in the paddock or how much forage it represents. IdeasFarm does not deliver it as a result: it runs it through the biological engine together with the other four sources.
| Biological Monitor | NDVI only | |
|---|---|---|
| What it delivers | Kilograms of dry matter per hectare, quality and grazing date | A greenness index, with no production units |
| Knows the crop | Uses the parameters of each species or mix | Cannot tell one species from another |
| Soil water | Keeps the daily water balance | Does not consider it |
| Management | Starts from your grazings, cuts and irrigations | Does not know when the paddock was grazed |
| Horizon | Projects growth and water risk | Describes what has already happened |
What the engine does with them
It simulates each paddock one day at a time. A sowing starts from zero; a regrowth, from the residual left after grazing.
- Phenological clockAccumulates useful temperature to determine which stage the crop is in. It counts how favorable the days were, not how many went by.
- Water balanceKeeps track of the water available to the roots. It detects when a deficit slows growth and when an excess leaves the soil without oxygen.
- GrowthStarts from the crop's potential and adjusts it for intercepted light, temperature, water and regrowth age. It deducts frost damage and respiration.
- CalibrationEach pasture measurement corrects the model toward your paddock's real productivity.
- Nutritional qualityEstimates how protein falls and fiber rises as the pasture matures, and weights the new regrowth against the old residual.
- IrrigationProjects soil water using the 48-hour rainfall forecast and issues one of four alerts.
The four water alerts
The parameters of each module are IdeasFarm's own and are configured per crop. The water balance follows the reference method of the FAO (Irrigation and Drainage Paper No. 56).
Accuracy and limits of the model
How accurate the estimate is and how best to read it.
Every measurement of forage biomass has a margin of error
No method can determine a paddock's dry matter exactly. Two people measuring the same paddock on the same day get different values, because the result depends on sampling. Cutting and weighing varies with the number and location of the samples; the rising plate meter, with its calibration for each species and season; and the satellite index loses sensitivity under dense cover and is interrupted by cloud.
The Biological Monitor reduces that uncertainty by combining independent sources: weather, satellite, crop parameters, water balance and management records. It is still a simulation model, and its accuracy depends on three factors.
- Quality of the inputs. The crop configuration, timely recording of grazings and irrigations, and the resolution of the weather data for the area.
- Factors the model does not observe. Soil fertility, pests, diseases, weeds and localized damage.
- Calibration with pasture measurements. Each recorded measurement adjusts the model's response to the paddock's real productivity. The more measurements, the smaller the deviation.
How to read it. The most reliable value is each paddock's trend and the comparison between paddocks, rather than the exact kilogram on a given day. IdeasFarm keeps the model under continuous development. It is a decision-support tool, to be checked against observation in the field.
What it is for, day to day
With technical judgment. The information from the Biological Monitor should be reviewed and cross-checked by the crop or livestock technician, or by the farm's advisor. They know the paddock, validate the estimate against what they see in the field and make the management decision.
Frequently asked questions
What is the Biological Monitor?
It is the IdeasFarm model that simulates each paddock day by day. It combines weather and satellite imagery, crop parameters, the soil water balance and your management records to estimate biomass, forage quality, the grazing window and irrigation needs.
Does NDVI measure a paddock's dry matter?
Not on its own. NDVI is a greenness index: it does not identify the crop or give kilograms of forage. The Biological Monitor uses it as one more variable in the model, alongside weather, water, crop and management.
Do I need sensors or a weather station?
No. The weather and the image of each paddock are obtained by satellite, based on the farm's location and your paddock map.
Does it work with any pasture?
You choose the crop or mix for each paddock from about 60 available options, and the model uses its parameters.
How often should I measure?
Regularly. Each measurement brings the model closer to what is happening in your field; without measurements, the estimate relies only on the weather and the crop's biology.
Continue with the paddock pasture measurement guide, the pasture measurement calculator or the IFI Index.