TOWN OF SCOTT
Based in part on research which shows an 89-percent boost in efficiency for crop scouting in large fields compared to traveling with a four-wheeler, the use of drones is becoming more popular in the agriculture sector.
That was the message from Zach Fiene of DMZ Aerial at a twilight meeting sponsored by the Sheboygan County Forage Council on the Mark and James Ramel families' Windy Hill Farms. Fiene and his brother Mitchell operate DMZ Aerial, a drone distributor based in Prairie du Sac.
Fiene, who has a background working for WinField (the crop division of Land O'Lakes) in southern Wisconsin and northern Illinois, said the use of drones is definitely a great time saver in crop scouting fields of 150 up to 600 acres. He noted drones are regularly flown in 15 states and a few provinces in Canada.
Most of the purchasers of the drone units suitable for crop scouting have been agricultural cooperatives, crop consultants and some equipment dealers, Fiene said. He knows of very few purchases by farmers themselves.
The drone unit, complete with all of the operating attachments, which Fiene demonstrated above a corn field bordering the lawn on the Ramel farmstead, sells for $4,500. Much more sophisticated drones sell for up to $60,000, he added.
Equipped with a camera that provides high-quality (4K) imagery resolution and allows zooming in on as little as a quarter of the image without reducing accuracy, the $4,500 unit is by far the most popular choice for agricultural use, Fiene said. Larger and more expensive units are designed for tracking cattle on large grazing ranches in the West.
The $4,500 unit comes with four batteries, each of which has enough power to fly the drone for a maximum of about 25 minutes. He said a flight to cover a field of 300 acres can be completed in about 17 to 19 minutes.
There is a capability to monitor the imagery in real time on 5- or 10-inch tablets, but the purposes of crop scouting are served best by downloading the data card to a cellphone, tablet or computer, Fiene pointed out. He also mentioned the option of a YouTube posting, which has a controlled direct access to assure data privacy.
Under Federal Aviation Administration rules, private drones are not allowed to fly at above 400 feet, Fiene said. The drones used for crop scouting start their flights at 200 to 400 feet and then can be maneuvered to hover at a height of only 10 feet in order to get a close look at suspected problem locations with the Go-Pro camera.
What Fiene described as "a gray area" pertains to how farmers are charged for services provided with a drone. Since the FAA prohibits the so-called "commercial use" of drones, the cooperatives and consultants using them are bundling the charges, typically at about $2 to $3 per acre, into what they are charging their clients for seed, scouting or products applied to the crops, he explained.
Other FAA guidelines are that the drones be operated only in non-populated areas and that a line of sight be maintained from the operator's base. This means in most cases the maximum range is one mile from the operating base, but this could be modified either by shutting off the distance limit regulator or by operating the drone from a moving vehicle, he said.
Having the drone crash is also a possibility, Fiene acknowledged. A tracker ($300) can be used to locate a downed unit. He reported that a drone that crashed in a pond was still operable when recovered about 10 minutes later.
The drones generally move at 20 to 25 miles per hour, Fiene said. Wind speed is usually not a deterrent to operating the drone but he said using it during rain is not a good idea because of likely distortions to the imagery.
That imagery is good enough to identity large insects such as Japanese beetles but not those as small as aphids or spider mites, Fiene noted. In most cases, the imagery will show discoloration of the crop, which indicates either a problem with disease or nutrients.
The goal is to identify differences in crop conditions based on light reflection, thereby allowing identification of plant stress when there still is time to take remedial crop management action, Fiene said. Infrared imagery, which is most expensive, can be used to predict crop growth problems rather than to verify those already occurring.
The more sophisticated retrievals of imagery are employed by seed research companies such as Pioneer and Monsanto, Fiene noted. With their crop plots, the options include cameras costing as much as $20,000.
To a question about what other types of data could be obtained with drones, Fiene mentioned the possibility of sensors collecting information other than the images that the technique allows today.
While the rotary drone Fiene demonstrated has a flight limit of about 25 minutes per trip, those with fixed wings can stay in the air for 45 minutes. He mentioned the possibility of covering up to 2,300 acres in a single flight with a more sophisticated unit.
A multi-spectral feature of the drone provides a geographical reference, Fiene pointed out. Other guidance is obtained from cell towers and from seven to 11 satellites that are integrated to operate the Global Positioning System.
Most people wanting to operate a drone with the mobile manual control device can learn the procedures in two or three lessons, Fiene said.
During the demonstration, he launched the drone from the lawn next to a corn field and sent it a couple hundred feet high and to a distance of a couple hundred over the corn field.
With Fiene at the controls, the drone stood in place or followed directions for changing course and altering its height. As he brought the unit back to base, it could be caught just as easily as a well-thrown Frisbee.
While it was in the air near the base, the field day attendees could see flashing green and red lights on the drone unit. The buzzing sound closely resembles that of a large fly at close range.