Farming by the Inch

With a show of hands, about half of those listening to the presentation in Jake Kraayenbrink’s back 40 near Moorefield, Ont., confessed to having a smartphone of some sort.

That means that half of the crowd at that manure management demonstration would instantly be able to pinpoint their location at that particular moment, in that particular field, using the global positioning system (GPS) feature on their smartphone. It also means that they may be only a step away from utilizing precision agriculture to manage their manure.
But what exactly is precision agriculture?

Simply put, it is farming by the inch instead of the acre. It is achieved by using satellite and sensor data in conjunction with computer software to map and manage field data and to generate distinct records for every field of the farm. The goal is to better manage resources.

The most common tool to achieve this is GPS technology, used on field equipment to accurately steer and control applications based on the position of the equipment in the field. Every operation done by the equipment can be mapped and managed as a business management tool.

“It’s pretty cool technology,” Larry Prong, GPS specialist with Premier Equipment in Elmira, Ont., told farmers. “It’s starting to become the norm to sell GPS equipment with new tractors.”

Precision agriculture components typically include a GPS receiver, an in-cab computer display, machine controls for guidance (commonly known as autosteer systems), spray controllers, rate controllers for dry box spreaders and flow meters for manure tankers. Other components may include field scouting devices and desktop geographic information systems (GIS) for data management.

But does precision agriculture technology have an application in manure management?

“Yes,” said Prong. “That’s the purpose of precision agriculture: getting more exact with our field operations and gaining the efficiencies through that.”

Using precision agriculture technology and tools can increase manure placement accuracy and application rates, but then the data can be sent back to the office to map your fields and help to keep good records as well.

When it comes to manure application, the placement accuracy you are looking for is probably six to eight inches, explained Prong. That’s good enough to make sure you don’t have any big skips as you move up and down the field, but make sure that at the same time you are not getting a lot of overlap.

One good example of where GPS accuracy would come into play in nutrient management would be side-dressing liquid manure into standing corn: it’s tricky and there is not a lot of room for error. Corn planted with high accuracy will have bullet-straight rows but, more importantly, you can go back exactly into same wheel track within one inch six or eight weeks later.

It’s Just Manure

Some people may say, “But it is just manure, why do we have to record all that data?

As your commercial fertilizer costs go up manure becomes liquid gold, said Prong, and there is tremendous value to what you’re putting on the land. If you’re going to take the time to work with an agronomist, you are expecting a certain yield from your ground and precision agriculture is just another piece of the puzzle.

Another side of the coin is that, unfortunately, manure is regarded as hazardous material. After the Walkerton incident, we need to know where it’s going down as well as setbacks from wellheads and waterways, said Prong. Every time you use a GPS system it provides an audit trail: this is how much I put down and this is where I put it down.

How Much Is Enough?

One of the key pieces of information is the amount of manure you’re putting down, which involves measuring not only amounts but also application rates. This is where a rate controller can be useful.

For solid manure, a rate controller gives you the ability to measure load size under a dry spreader box, measuring change in weight to calculate the application rate. A hydraulic gate valve can then help regulate the amounts going on the field.
Prong said liquid manure measurement requires the use of a flow meter, a common feature nowadays that will measure liquid manure application in gallons per minute from the tanker.

“That’s important in injected manure where you can’t see what’s going in the ground,” he said. “It’s amazing how a change in ground speed can spike your application rates.”

For example, at four miles per hour with a 2,500-gallon-per-acre target flow, 300 gallons per minute will be applied. Keeping the same flow but dropping to three miles per hour, that application rate will now be 3,300 gallons per acre. That’s a 30 per cent increase in application rate just by slowing down, and that decrease in speed can be caused by something as simple as going up a hill.

Premier Equipment has developed a creative solution that integrates an application rate control system with the IVT transmission of many John Deere tractors. As Prong explained, their rate controller actively adjusts the transmission of the tractor to maintain a consistent ground speed, which is highly critical in a dragline scenario for maintaining a consistent application rate.

Software

In precision agriculture, as the technology is used, maps of your fields are created, allowing you to define and record not only where you’re putting down manure but how much you’re putting down. When you need to calculate how much commercial fertilizer to use above and beyond just manure, you’ll have accurate data. “That’s a plus for nutrient management,” said Prong.

Whether you have a GPS in your tractor, carry it in the phone on your belt or take it out on the four-wheeler to chart your fields, you’ll still need software to process and organize the data. The records from the field will also need to be stored and accessible, as you will need to go back and analyze that information over time, both in the short term and over several years.

A number of software products are available, and even more are still in development. Farm Works software has released the Connected Farm app, which runs on iPhones and Android smartphones and allows field scouting with a GPS-enabled smartphone.

Data can be transferred from the tractor using a memory stick, but when you use wireless technology, that transfer can be done while out in the field. As soon as the manure is put down, the data can be sent wirelessly to the office desktop computer and the software will automatically recognize and file it, including the geographical locations in the field.

“Quite a few people haven’t gotten there yet – they’re physically moving their data from the tractor to the desktop, but I think this is the next step in precision agriculture,” said Prong.

Looking to the future, he predicts that the next advancements will be in wireless transmission and software improvements.