by the Lockwood Maufacturing Team. Republished here with permission.
If you’ve been in the potato business for any time at all, you probably have an excellent understanding of your own harvesting equipment. However, because growers are often only familiar with what they themselves use, you may not realize how many money- and effort-saving options now exist in harvesting technology.
Today’s spade blades come in multiple options (clod, semi-clod, combo, etc.). It goes without saying that the right choice depends on harvest conditions; still, it’s often surprising to learn how many growers don’t employ the best blade for their specific field and conditions.
Harvest conditions also influence the type of cleaning technology required prior to storage/shipping. Harvesting in light, free-flowing soils is inherently easier than harvesting in heavy, clod-prone or rocky soils. In sandy, rock-free soils, some growers can get away with direct loading without prior dirt and debris management. In all other soils, however, cleaning is a vital priority handled by the multiple turns and controlled drops aboard conventional and air harvesters.
Shakers, traditionally only at the primaries but now optionally available at the secondaries, remove the bulk of loose and clumped dirt via opening and closing chains over rollers. Some manufacturers, Lockwood included, now offer tables in the secondaries with rubber-covered or steel rollers that can be spaced according to conditions. These rollers break stubborn clods and heavy dirt without bruising the tubers. Though effective, the technology does depend on the operator correctly controlling speed to ensure that the potatoes ‘ripple’ above the top of the rollers rather than bumping along washboard style.
Following the shaker tables, most harvesters today offer high-velocity air. Initially, blowers appeared on harvesters to manage the debris left when vines were chopped prior to harvest. Today, an airstream of either negative (vacuum-pressure) or positive (blowing) air carries the tubers while heavier rocks drop out below. Air heads are a costly addition to a potato operation because they require independent engines or large tractors to run. The good news is that while air heads have been on the market for about 30 years, we’ve recently seen significant improvement in their fuel efficiency.
Harvesters without full-width cleaning tables at the secondaries typically have side-elevator cleaning tables. It’s worth doing some homework on the tables available today, since they now come in almost a dozen different sizes and functions. Look, too, at the new kinds of enhanced rubber, C-flex and pillow-style protection available for most moving parts, designed to mitigate tuber nicking, skinning and bruising.
Lockwood engineers estimate about 50 per cent of growers — generally only those in very sandy conditions — currently windrow ahead of their harvesters. Windrowing allows the digging of more rows in less time: some growers run 6-row windrowers on either side of a 4-row harvester, digging a total of 16 rows in a single pass.
The speed gain of windrowing is offset, however, by the need for additional tractors and operators to run the extra machines. And, because the crop is harvested much faster, growers who windrow often require more trucks to transport the crop out of the field. The key to success with windrowing is to balance the quantity of product entering each side of a harvester. Unbalanced loading translates to the machine over-cleaning and ultimately damaging potatoes on the more lightly loaded side.
The moments surrounding harvest are vital to both tuber quality and cleanliness. Staying up-to-date on improving technology and choosing the right equipment for your unique conditions is key to maximizing the value of your crop.