Gold to green
Article Images (Click for larger view)
Automatic burley harvester promises to reduce labor by 85 percent.
Submitted by GCH International Inc.
More than two decades ago, engineers at the University of Kentucky’s Department of Biosystems and Agricultural Engineering developed a mechanical harvesting system to reduce labor needs for burley tobacco operations. At that time, growers faced uncertain and decreasing availability of domestic laborers. But by the time the first prototype—affectionately known as “Big Red” because of its colorful paint job—was tested in 1985, a major change occurred whereby a migrant labor force became available to sustain the conventional harvesting system. This newfound labor supply eased growers’ interest in mechanical harvesting systems.
Nevertheless, development continued and an improved prototype system was tested in 1994 as engineers tried to reduce the 65 man-hours per acre needed in the conventional, labor-intensive harvesting process.
Now, with labor costs soaring, machinery manufacturers have shown an increased interest in bringing burley farmers an automated, machine-driven harvest solution. One of these companies, GCH International Inc., has acquired the rights to market and manufacture the system originally developed in Kentucky.
The new systems will be painted harvest gold, says Jeff Androla, president of GCH. “We’re hoping that these gold [systems] will be able to put a little green in farmers’ pockets.”
The company has continued to refine the prototype. “A lot of field testing was necessary,” Androla says. “Notching the stalk on a corner so that it slides down the rail just right was the most difficult part of the process.”
The company has sold three units in the U.S. so far, which are the first production units. At press time, these units were nearing completion but had not yet been delivered to the first customers.
The harvest system was designed to harvest whole burley plants with minimal leaf damage or loss and place them into portable curing frames for outdoor air curing, the goal being to provide a quality product equal to conventional barn-cured burley.
The complete system, yet to be named by the company, consists of the harvester, the racks, a specially designed trailer and an implement for the racks that mounts on a front end loader.
Here’s how it works: A self-propelled harvester—operated by one worker—automatically follows a standing row of plants. Plants are cut near ground level and grasped by opposed gripper chains in the header. The header elevates the plants and inverts them 180 degrees to be hung for curing. Once inverted, opposed notches are cut near the base of each plant, and they are inserted into slotted metal rails spaced 3 inches apart.
Eight metal rails, 14 feet long, are mounted in portable steel curing frames at 12-inch spacing. After the rails are sequentially filled with plants, support legs are rotated down 90 degrees from their stowed configuration, and the filled portable curing frame is off-loaded from the harvester. The harvester carries five empty portable curing frames that are loaded by a tractor front loader equipped with a special handling device. Fifteen portable curing frames are required per acre. Each rack holds about 2,500 pounds of fresh cut tobacco.
The harvester cuts approximately 2.5 plants per second and the maximum demonstrated harvest rate is approximately five acres per day, depending on field conditions and supporting equipment. Two workers are required to operate the system, one to operate the harvester and a second to operate the tractor loader delivering empty curing frames to the harvester. The second worker can also operate a tractor-drawn mechanism that retrieves filled curing frames from the field and places them in a convenient location and arrangement for curing. Filled frames remain exposed to weather for one week, then fitted waterproof coverings are placed on the frames. Tobacco cures in approximately five weeks and is ready for market preparation. Leaf loss associated with the system has been approximately equivalent to manual harvesting, varying between 2 and 4 percent depending upon plant turgidity. Plant loss varies between 1 and 2 percent depending upon the degree of lodging. Quality of tobacco cured in the portable frames has consistently equaled or exceeded that of tobacco cured in conventional curing barns.
Approximately 10 labor hours are required per acre harvested with the system, reducing labor requirements approximately 85 percent per acre. The annual capacity of a harvester will be approximately 200 acres (five acres per day for 40 days), thus the annual cost of the harvester per acre should be relatively low. The comparative cost of portable curing frames versus construction of new curing barns will be a key factor in determining adoption of the system.
Besides substantially reducing labor required in conventional harvesting, the system is totally portable and can be moved to any location. Other advantages to the system are dependability, predictability, manageability and safety.
Post quota burley production has been limited by scarcity of conventional curing barns. Future availability and cost of labor for conventional harvesting is uncertain. Such conditions should continue to narrow the difference in cost between this system and conventional harvesting, whether it is purchased directly by growers (individually or cooperatively) or supplied by contractors.
The system harvests and cures whole burley plants. No differentiation is made between leaf grades or healthy versus unhealthy plants. The system does not alter leaves in any way. Virtually no non-tobacco-related materials (NTRMs) are mixed with tobacco plants harvested by the system except occasional large weeds that may be encountered within the plant row. These weeds are easily discarded when cured plants are removed from the portable curing frames.
The harvester is equipped with lights and can operate at night. Acceptable operation is generally determined by plant turgidity. Harvesting in rain would likely increase plant turgidity and result in excessive leaf breakage.
Androla also hinted at a new system the company is developing that would remove the stalk from the rail and strip the leaf automatically. Combined with the harvesting system, this new system would allow for a complete harvest without a human hand ever touching the leaf. How soon could growers expect this? “We’re pretty far along in development,” is all he would say.