The corn planter is one of the most expensive implements that a farmer can own. Not that it necessarily has the highest initial cost, but from the fact it only accomplishes one function (planting corn) and thus is only used on a limited number of acres per year. This makes the per acre cost of ownership very high compared to many other implements. Although the corn planter only performs one function, it is an extremely important one and for this reason the planter deserves careful attention to maintenance for good stand establishment and to protect your investment. Now is the time to make sure your planter is ready for spring.
Research studies have shown that a planter which is out of adjustment and operated at too high a speed can cut corn yields by up to 20 bushels per acre. Some of the important factors related to yield loss include planting less than desired number of seeds per acre, variable in-row seed placement, improper planting depth, and poor seed to soil contact.
The operator's manual contains the information needed to determine the seeding rate for various sprocket combinations and row spacings. This is based on a particular tire size and pressure. If your tire size or pressure are different than those listed in the manual, seeding rates will also be different.
Uniform seed placement within the row is also important to obtain maximum yields. Research at the University of Wisconsin and Purdue University has documented that corn plants next to a gap in the row may produce larger ears to help compensate for missing plants, however, these plants cannot make-up for those that are crowded as "doubles" or "triples". Plants placed too closely together in a row will compete ineffectively for sunlight, water, and nutrients. Crowding often results in barren plants or ears too small to be harvested. In a survey of Indiana corn fields several years ago, it was determined that growers could improve grain yield anywhere from 4 to 12 bushels per acre if within-row spacing were improved to the best possible uniformity. Plant spacing variability is often related to misadjusted or malfunctioning planter mechanisms. With finger-pickup style planters, double or triple drops may occur from worn finger-pickup mechanisms, mis-adjusted finger tension, worn knockoff brushes, or from driving too fast.
Another important planter component to check before hitting the fields this spring are the double disk furrow openers. The two disks should have about two inches of contact at the point they enter the soil during operation. If the length of contact is less or if they do not touch at all, the "V" shaped seed furrow will be replaced by a "W" furrow. This will impact seeding depth and seed-soil contact. In no-till conditions, it will also reduce penetration into the soil crust. Finally, once planting time arrives, make sure to operate the planter within the specified speed range. Planting too fast can cause even the best adjusted planter to perform below optimum in terms of seeding depth, placement, and uniformity.
For more information contact Mike Rankin|
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