Variable rate prescriptions | Computer program uses satellite images to create field maps for soil variability and yield potential
WOODSTOCK, Ont. — A crop input company has figured out how to use satellite photos to help producers better manage their farms.
Winfield’s R7 Tool is a computer program that uses a historical database of satellite images to create field maps, including soil variability, management zones, yield potential, and profitability maps.
Colin Smith, the company’s sales rep in Ontario, said the maps provide information on fields that wouldn’t otherwise be available, even to agronomists who have worked with the fields for years.
“I’m able to see aspects of the field that the agronomist, without this data, has never seen before,” he said.
“It becomes a different discussion. You can do a better job selecting a better product and population for that field.”
The first step in analyzing a field is to map it on a satellite image within the program. Producers then select the crop to be planted and the product to be used.
The program provides product scores on measures of response to population, response to nitrogen and how products respond on a continuous corn rotation.
The program then searches the database and selects maps from two drier than average years and two wetter than average years.
It then creates a soil variability map, which shows where the heavier and lighter soil is located in the field.
The program examines the variability in the foliage of previous crops, identifies trends in biomass levels across the fields and creates yield potential maps.
Producers involved in variable rate planting and fertilizing will be interested in the satellite derived management zones (SAMZ) map the program creates, which breaks the field up into management zones.
“It’s showing that there are different zones in the field,” Smith said.
“Not that one is better than the other, but on the data it’s looking at, they are significantly different and should be managed accordingly.”
Information from the combine’s yield monitor can be imported into the program and overlaid with the SAMZ map. Producers can then use this information to check how their variable rate seeding and fertilizing program is working.
“We can basically ground truth what has happened in that field and start making finer adjustments for the following year,” Smith said.
The SAMZ map zones can also help producers decide where to soil test.
R7 Tool can also create profitability maps. Producers enter input costs for the different products used on a field and then import their yield data into the map to see which acres are most and least profitable.
“In some of those lower producing acres, rather than over fertilizing them, it might be a situation where we can move that fertilizer to an acre that’s going to be more responsive,” Smith said.
“We’re not going to spend any more money on fertilizer, we’re just going to reallocate the resource to get more return for it.”
Growers can also buy in-season images to help scout their fields. The in-season image can be imported into the program and then exported to Google Earth on the producer’s smartphone or tablet. The user can then walk directly to a problem spot to look for the causes of field variability identified on the map.
R7 Tool is also used to identify which corn and soybeans will work best on a field. Different maturity lengths are input into the program and soil types accounted for. It also considers how the product responds under different management, such as row spacing and plant population.
The archive maps are part of a service that Winfield sellers provide. However, prescription or variable-rate planting maps currently costs $7 an acre. The price of an in-season image is also $7 an acre. The suggested retail is $12 an acre if both products are purchased.