With the increasing use of precision technology in agriculture -- especially with the coming employment of unmanned aerial vehicles (UAVs) – electronic sensors, both soil moisture and crop monitoring, have become key tools.
Among researchers studying crop monitoring sensors is USDA-ARS agricultural engineer Earl Vories. Vories, who works out of the Missouri Agricultural Experiment Station Delta Research Center (http://delta.cafnr.org/) in Portageville, spoke at the station’s recent field day.
What are you trying to accomplish with the sensors?
“We’re part of a large group that is working in several states on use of crop sensors. There are people that have been working with sensors a lot longer than I have.
“My involvement began with using them for nitrogen management. There has been a lot of work on wheat and corn. When I joined ARS I was invited to work on some of the corn studies and then started looking into applying it to cotton.
“Cotton Incorporated brought researchers together yearly to meet and compare notes to push the research forward.
“The sensors are technologically sound and I believe they will make a big difference -- especially with the increasing use of UAVs, or drones. Those will be used in agriculture more and more and will carry more kinds of sensors.
“We’re now at the point where we have quality sensors that are small enough, portable enough, to be mounted on tractors, sprayers and the like. Looking at applications for those, nitrogen was something that was a good fit. I’m still working on that with (Missouri cotton specialist) Andrea Jones and others.”
How do they work?
“First, let me narrow it down a bit because there’s a wide range of things that fall under the term ‘sensors.’ For instance, on our tractor this year we were collecting data, we were measuring reflectance, plant height and crop temperature. All those were collected at the same time.
“While we’re using the sensors on a tractor driving through a field, others mount them on center-pivots and collect data as the pivot walks through the field.
“We’re not all using the same type of sensors. Even when we’re collecting reflectance data or calculating NDVI, we’re making use of different brands. Many are equally reliable.
“The way we do it is save the data onto a computer as we drive through a field. We’re not using it for real-time management. The sensors could easily be connected to the internet or have a cell phone connection and monitored and communicated that way. Some of the center-pivot research is using that information to check crop temperatures to know when to turn on the pivot.
“With real-time nitrogen management, the sensors on front of the machine and an on-board computer calculate how much nitrogen needs to be applied. The applicator is on the back of the vehicle and it releases the exact amount of nitrogen as you drive through the field based on the sensor readings. That’s the long-term goal -- to get to real-time management.”
Brands, UAVs, questions
Are the sensors capable of communicating between brands?
“Someone in our group is writing the software we use. That means we can mix and match brands and types of sensors. A farmer or consultant probably doesn’t have someone experienced in working with instrumentation and software and may need to stick with a sole company. For our research that isn’t a hindrance, though. It allows us extra flexibility to add more sensors.”
How will the UAVs play into this?
“It’s kind of hard to make exact predications. The reason is the regulations around UAVs are still being developed. It’s hard to speculate when we still don’t know the rules.
“However, it’s reasonably assured that we’ll be able to use them in agriculture. When I speak with students, I tell them one of my goals is to develop something with the tractor-mounted system that can translate to use by a UAV. It may have to be smaller and more power-efficient because of weight limitations. But that’s the goal.
“UAVs are certainly a hot topic right now. At most field days lately there seems to be someone talking about UAVs and their future impact. Once the FAA settles on regulations, I think there will be many more farmers buying them. I know a lot already have them but many are waiting to see what the rules are. Consultants want them, as well.
“It’s very important for farmers and consultants to be educated on sensor use. But it’s also important that they know what the limits are. For example, if the sensor isn’t calibrated or aimed properly, you won’t get good data. If you spend a lot of money applying nitrogen based on faulty data, it’s probably not going to help you.”
Typical questions you get?
“Mostly farmers just want to know that the sensors will work. They want to be assured that they’re not spending money on something that won’t pay for itself.
“But even with that hesitation they’re eager to use them. At the same time, we’re eager to provide the information they need to be successful.”