- Excessive rainfall can make nutrient management more complicated for farmers
- Yara’s Atfarm system can help make farmers’ lives easier and enables them to make more informed management decisions
- Functionalities within Atfarm help farmers optimise their fertiliser applications
Precision may be vital but factors like wet weather can make this more complicated for farmers. Natalie Wood, Yara’s Agronomy Operations Manager, discusses how Yara’s Atfarm system helps make farmers’ lives easier and enables them to make better management decisions. Particularly when it comes to fertiliser applications.
Excessive rainfall can make it difficult for farmers to calculate exactly what nutrients their crops need. The very wet autumn and winter has meant soils have been without oxygen, and anaerobic soil conditions means farmers need to think differently about managing their crop nutrition. The good news for them is that tools like Atfarm take away the guesswork.
“We don’t necessarily know how much mineralisation has happened over winter due to different factors such as the temperature and amount of rainfall,” says Natalie. “However, we can use systems like Atfarm and the tools within it to get a definitive value about how much mineralisation there is, or how much nitrogen is left in the soil. This then allows farmers to make a more informed decision and helps them choose their nitrogen rate accordingly.”
As a key period in this season’s crop nutrition programme approaches, farmers can utilise key functionalities within Atfarm to improve nutrient use efficiency and achieve healthy yields.
“There are quite a few functionalities within Atfarm itself,” explains Natalie. “There are various ways that you can look at your biomass and mapping of your fields, including variable rate mapping, and you can also use tools like the N -Tester, which will give you that definitive value in terms of what your crop has taken up and a nitrogen recommendation based on that. Farmers can use these tools to grow homogenous crops and to improve overall nutrient use efficiency after what has been a difficult start to the season.”
Atfarm isn’t something that’s brand new. The algorithms and the precise calculations it provides for farmers are the result of over 20 years of research.
“The actual algorithm that we use within Atfarm for the variable rate application maps comes from the N-Sensor technology that we’ve had for over 20 years now,” says Natalie. “We’ve gathered a lot of data over that time which we feed back into the software, year on year.”
Using the N-Sensor technology helps farmers get the most out of satellite maps. Rather than just using NDVI (Normalised Difference Vegetation Index) to assess the health and density of vegetation with its nine different shades of green, N-Sensor can detect 27 different colours. This provides farmers with a lot more information on nitrogen uptake throughout the growth cycle and across seasons.
Another key part of the Atfarm toolbox for this stage in the growing season is N-Tester. The N-tester looks at the level of chlorophyll in the plant and, as this directly relates to the amount of nitrogen, farmers can better determine nitrogen levels in the crop.
“To determine the amount of chlorophyll in the plant, you pinch the leaf between the sensor, and it looks at the amount of light that goes through it and picks up the different wavelengths that are relevant for chlorophyll,” says Natalie. “That will also tell you how much nitrogen is in the crop as they are related, and you can get a recommendation based on the level that’s in the crop.”
When using the N-Tester device, Natalie recommends taking at least 30 non-destructive samples to get a representative analysis across the field.
“Do it just like a soil sample in that W shape to get a good representative sample,” says Natalie. “Though if you’ve got very different soil types or a good area versus a poor area, then you treat them differently. Take samples in the poor area, samples in the good area, and then either use the average or play around and do some variable rate on either of those sides.”
Within Atfarm, farmers can create variable rate maps which they can use as a visual aid to help them homogenise crop growth. There’s a standard NDVI map, an optimised map which uses N-Sensor technology, and a nitrogen uptake map; all of which can help with variable fertiliser application.
“What we don’t want are poorer areas being under fertilised and conversely areas where we are putting too much nitrogen on,” says Natalie. “What the software does is create a variability map with different colours denoting the levels of variation. There are different options such as levelling where you can apply more nitrogen to the poorer areas, or you can select protein applications to boost all the areas up to a certain level.”
Another thing farmers need to do within the variability map is set their target rate. “So, for example if you wanted to apply 80 kilos of nitrogen, you’ll have your target rate at 80 and then it will ask you to set some upper and lower limits,” explains Natalie. “If you’ve got quite a variable field, you’ll want to set those quite widely to try and even it up.”
To get more information on Atfarm or sign up, the easiest way is go to app.at.farm. Sign-up is free and it’s a great way to take your first steps into precision nitrogen applications.
“Log on, have a go, add a field and see what you think of the system,” says Natalie. “It’s a great way into precision nitrogen applications because you don’t necessarily need to spend money on big pieces of kit. You’ve got that variability map that you plug straight in if you have got that variable rate option on your spreader.”
Related news: