Editor: Photos are available. Please contact Candace Pollock at (330) 202-3550 or pollock.58@osu.edu.
COLUMBUS, Ohio - Precision agriculture techniques, generally applied to field crops such as corn and soybeans, are being used to improve production of high value commodity crops.
Ohio State University agricultural engineers have developed a mechanical strawberry yield monitor system prototype that accurately measures fruit yield as the crop is being harvested. It can also be connected to a GPS (Global Positioning System) to create yield maps that document field yield variability.
Reza Ehsani, an Ohio State precision agriculture state specialist and one of the project researchers, said the device could be used as a management tool to increase profits.
"The yield monitor has the ability to quantify yield variability on a farm with the help of GPS. If the variability is too much, then a farmer can search for the cause, like disease or lack of soil nutrients, or pests, and can then manage his field accordingly on a site-specific basis," said Ehsani. "Strawberries are such a high value crop. They have a better return per acre than corn or soybeans, but lack of an appropriate yield monitor and smaller farm size have caused precision agriculture technology to be generally ignored. At least in theory it just makes more sense to use that technology for high value crops. The more accurately you can manage your field the more you can increase your profits." The yield monitor is designed to install on a strawberry harvesting aid machine. Apart from the GPS system, it acts as a scale that measures the weight of the strawberries as they are placed on the monitor. When the batch reaches a specific weight, a pound for example, the monitor then dumps the strawberries into an appropriate container that is then packaged for sale. The system, simple and low in cost, effectively measures yields as the crop is being harvested.
Ehsani said that although it is possible to measure yield manually in the field, it is time consuming and infeasible. "If a farmer has 10 acres and measures his yield manually every three feet by three feet, it's technically impractical," he said. "That's just too time consuming." A strawberry harvesting aid machine, most commonly found in Florida and California where large strawberry production takes place, has not been designed for use in the Midwest. But Matt Sullivan, an OSU Extension program specialist, helped develop a semi-automatic mechanical harvesting aid machine for use on his 15-acre family strawberry farm near Columbus, and has been pleased with the results.
"On our farm we are finding that new production systems and cultivars enable running a semi-automatic mechanical harvesting aid possible, " said Sullivan.
The harvesting aid machine houses a platform on each side of the machine where pickers sit and harvest strawberries as the operator drives the machine through the field. The strawberries are then placed on a conveyor belt, located in the middle of the harvesting aid, and are carried to the back of the machine where another person inspects the berries and then dumps them in the yield monitor to be measured and then packaged.
Sullivan said the harvesting aid machine improves efficiency by decreasing the time it takes to harvest a field and saves on labor costs, since it only takes half the number of people to harvest using the machine than to do it by hand.
"We are also selling a higher quality berry for the consumer because there are several people on the machine who evaluate the berry before it gets packaged," said Sullivan. "Quality control is one of the biggest issues when harvesting berries." Sullivan's family has used the harvesting aid machine for two years to pick and plant strawberries and cultivate other crops. "I think this machine has really improved our production and our yields," said Sullivan. The family plans to use the harvesting aid machine for other research projects, such as evaluating production systems and cultivars that best fit their agricultural practices.