IT CAN BE challenging to determine exactly what nutrients each crop needs and when. Equally challenging can be establishing the value of manure or other land-applied nutrients and how to best maximize that value on-farm.
To address that issue, a new collection of online calculators has just been launched that can help farmers determine how to get the most out of farm or municipal nutrients. They belong to AgriSuite, the provincial government’s agricultural and environmental software package, and were recently added as part of an overall modernization of the system to make it easier to use and more compatible with industry needs.
The five easy-to-use calculators can be used independently or in tandem to obtain simple estimates to support nutrient management decisions. Topics include field management plan, organic amendments, phosphorous loss, fertilizer, and crop nutrients.
“AgriSuite is designed to give Ontario farmers a versatile set of tools that will help them make the best possible soil management decisions on their farms,” says Christine Brown, field crop sustainability specialist with the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA).
CROP NUTRIENT CALCULATOR
This calculator provides agronomic crop nutrient requirements (N-P-K) based on soil test values, yield goal, and location information entered by the user for each field. It will also estimate the amount of nutrients removed from a field by a specific crop.
FIELD MANAGEMENT PLAN CALCULATOR
This tool helps determine a crop’s nutrient balance by considering nutrients from organic amendments, commercial fertilizer, and previous nitrogen credits. This is important to help keep soil productive while minimizing the risk of nutrient losses that could be harmful to the environment, notes Brown. The calculator uses field location and site details to help in its analysis, as well as nutrients removed through the previous harvest.
This tool provides the total commercial fertilizer applied to a single field or will calculate the blend of fertilizer (N-P-K and micronutrients) needed to complement nutrients already provided (through manure, for example) to best meet the needs of a specific crop.
ORGANIC AMENDMENT CALCULATOR
This calculator will help farmers get a better understanding of the nutrients supplied by manure applied on the fields. It calculates the amount of crop-available nitrogen, potassium, phosphorus, and applied micronutrients for each proposed application of organic amendments. It will also estimate the fertilizer equivalent value of each manure N-P-K application and allows quick comparisons of the impacts of different timing or placement scenarios for estimated available nutrients.
“Nutrients from organic sources don’t come in pre-determined blends, so this calculator helps take the guess work out of available nutrients,” Brown says.
PHOSPHORUS LOSS ASSESSMENT TOOL FOR ONTARIO (PLATO)
Phosphorus is an important plant nutrient for crop production, but it can also contribute to environmental problems when it ends up in rivers, lakes, and streams. That’s why decisions around how phosphorus is applied at what rate and what time and from what source are important when fertilizing a crop. The PLATO calculator helps determine the risk of field-scale phosphorus based on site-specific characteristics and management practices, factoring in soil erosion and soil test levels, phosphorus application amounts, and application timing.
Additional calculators that are also part of AgriSuite are currently being updated. A series of workshops on how to use the tools has just been completed for dairy, hog, and poultry producers. Keep an eye open for new workshops for all types of organic amendments coming soon.
The entire collection of tools, which is free to use, is available at www.ontario.ca/agrisuite.
This article is provided by Farm & Food Care Ontario as part of the Timing Matters project. The project is funded by the Ontario Ministry of Agriculture, Food and Rural Affairs. •