Let’s get digital
Maximizing nutrient use through digital tools.
February 28, 2023 by Richard Kaschen
Whether you’re a grower who applies manure to your crops yourself, or you’re a custom applicator for hire, knowing the right amounts, timing and storage solutions can mean all the difference in the world, from higher yields to increased quality. For that reason, growers and applicators are always looking to maximize their nutrients.
The Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) has spent the last several years upping its game to bolster its suite of digital tools. It now offers producers and consultants “AgriSuite,” a host of free, voluntary web-based support tools developed by the provincial department – with components that expand beyond the borders of the province.
“The tools are meant to help with nutrient management decision-making,” explains Christine Brown, OMAFRA field crops sustainability specialist. “They allow users to get an idea of nutrient efficiencies and environmental losses. It lets them try different management practices at the click of a button.”
AgriSuite also assists farmers in fully crediting the nutrients they get from manure and where to best target their nutrient dollars.
“It’s fine-tuning the efficiency of the nutrients because it looks at what the balance is over the rotation, and looking at what the approximate nutrients are that you’re getting from manure,” says Brown.
Organic amendment tool
“It’s basically a manure calculator,” says Brown. This tool helps determine nutrients supplied from manure inputs by calculating the amount of available nitrogen, phosphorus and potassium (N-P-K) and micronutrients supplied from a manure analysis. This could be provided by the farmer or from a database of samples.
The database is extensive: pig and dairy manure each have more than 2,200 samples to choose from. It can also be fine-tuned.
“If you’ve got sows, you would have a much more watery manure – less dry matter – than if you’ve got finisher manure. So they can choose those dry matter levels,” says Brown. “Eventually, we’re going to have an option where people can pick finishers or sows or farrow-to-finish. That’s coming in an upcoming release.”
Growers can also choose application timing – spring, fall or late fall — and incorporation details, such as if the manure’s injected, incorporated same-day, after two days or not at all. They can also specify if it’s applied to a growing crop or residue.
Also included in the calculation is the manure application rate. This is interchangeable for metric, imperial, or U.S. units.
The results provide projected available nutrients and an estimated economic value (N-P-K equivalent after application).
“This helps people put a value to manure, that it’s not just a waste product,” says Brown. “This hopefully helps put the manure in the fields where those nutrients are needed the most.”
This tool isn’t limited to Ontario and can be applied in any region, she adds.
Crop nutrient and fertilizer calculators
AgriSuite’s crop nutrient support tool provides N-P-K recommendations based on soil test values, geographic location and nitrogen credits from the previous crop, as well as estimated nutrient removal based on yield goals.
This helps growers determine the amount of nutrients they’ll need to maximize economic crop yields.
Meanwhile, AgriSuite’s fertilizer calculator helps ascertain total nutrients from applied commercial fertilizers, and the commercial fertilizer required, before or after manure nutrients are worked out. It’s intended to ensure crop needs have been met and prevent overapplication, while also providing a blend of commercial nutrients to meet crop needs not supplied by manure.
Field management plan
“What we did is we provided these nutrient management tools so that they were standalone tools and could be combined into more comprehensive tools,” Brown says.
The AgriSuite field management plan layers a number of calculators, including the ones described above for manure, crop nutrients and fertilizer.
“It allows the user to input the full crop rotation, all the different timings within the rotation of where fertilizer or organic amendments are applied, and then at the end of the day seeing whether they are in a rotation nutrient deficit or surplus, and how that impacts the soil fertility levels for that site or field,” explains Brown. “The layering in the field management plan lets the producer determine where they still need to add more fertilizer, or where they can potentially move manure to fields with higher fertilizer needs, or sell manure to a neighbour and make some additional profits.”
The field management plan will alert, or flag, users applying too much or too little fertilizer.
“If we apply more than 200 pounds of nitrogen and the crop doesn’t need that much, it will give you a red BMP flag, with a comment, ‘The total nitrogen applied exceeds 200 pounds per acre,’” says Brown.
The field management plan also provides a new, recently added tool that calculates average greenhouse gas emissions based on user-provided information.
Manure storage and sizing
This AgriSuite tool helps users plan and size the infrastructure they’ll need to store all nutrient-rich materials generated on their operations.
“You can choose storage type and input what the dimensions are, and it will give the days of storage, total capacity, material capacity and rainfall capacity,” says Brown. “It shows approximately how much manure is produced by specific animal type and numbers, approximate dry matter of that manure, and also suggests nutrient units, and estimated livestock barn area that’s required.”
Not confined to Ontario’s borders, this tool provides units in both cubic feet and gallons per day.
The tool can account for changing livestock numbers, and also offers the option of adding treatments like solid/liquid separator, composting system, in-barn active composting, sand separator and anaerobic digesters.
Greenhouse gas calculator
The greenhouse gas (GHG) decision support tool estimates greenhouse gas emissions from crop and livestock operations, and allows users to test how different management practices could reduce emissions and sequester carbon.
“It can show differences being made with beneficial management practices like cover crops, rotations with forages or wheat, or no-till,” says Brown.
She stresses this is only meant to be an educational tool, and not to assist in receiving carbon credit dollars.
OMAFRA plans to eventually tie the calculator to the field management plan.
“We will have a button in the field management plan where we’re going to have a ‘Do you want to convert this to a greenhouse gas calculator?’ so that you don’t have to input all the data over again. We’re not quite there yet.”
AgriSuite users are advised that the tools provided should be considered guidelines only. “No two farms are identical,” says Brown. “There are no soil or weather conditions that are going to be the same at every location, every year. All of those impact crop nutrient uptake and losses, so the tool’s never going to be 100 percent accurate.”
The new GHG calculator should be seen in the same light. Updates happen quickly as new research becomes available. Its purpose is to demonstrate to users where carbon dioxide, methane and nitrous oxide losses occur, and how different management practices compare in their impact on greenhouse gas emissions.
Originally aimed at consultants undertaking nutrient management plans for farms, AgriSuite has been re-done and re-located to a new platform. The new version is accessible via smartphone, tablet and PC.
Currently, no offline options are available, but OMAFRA is considering future opportunities there.
Users needn’t create an account to access most of the tools, but can’t save or access previous work without one. •