Today's Planters and Planter Maintenance Score Well
Farmers show they've learned value of equal spacing and the equipment is helping too.
Tom Bechman
Published: Nov 29, 2010
You will read about experiments this winter where driving six miles per hour yielded just as well as five and four miles per hour. You'll also read how the spacing isn't as good. But the difference between now and 10 years ago is that even when driving faster than you should, most planters can compensate enough that the spacing variability is small enough that it doesn't affect yield.
Bob Nielsen, Purdue University corn specialist, prefers a maximum of 2 inches in standard deviation. That means stands are two inches from being perfect, in layman's terms. Yield losses begin to accumulate at about standard deviations of 3. In the days before Nielsen emphasized planter maintenance and the importance of placing plants evenly, standard deviations of 3, 4 and even 5 were relatively common. In a recent experiment, 6 miles per hour produced a significantly more irregular stand, but its' standard deviation was still only 2.5. So when it came to yield, there was no difference. Actually, the plot planted six miles per hour yielded most, although the difference wasn't significantly different at the 0.1 least significant difference level of confidence.
Why would standard deviations be lower today? Several factors are possible. Nielsen held many meetings on the subject, and it was well-publicized in the press. The farm press continues to carry articles about the importance of good, picket-fence type stands.
Secondly, meter test stands have become popular over the past 10 to 15 years. For a small fee, it's now convenient for people to have their units run on the stand and inspected each year. Not only are worn parts replaced, but if adjustments are made or on vacuum planters, if air adjustment needs to matched to seed grades, that's much more likely to happen today that it was even five years ago.
Third, today's hybrids as a whole have a better emergence and vigor package. Many also are treated with more powerful insecticides and fungicides to protect against seedling pests that might attack the seed than in the past. The result is that a higher percentage of what's planted also comes up. Plants that come up and die and are gone before stand counts are made go down as a planting error when you're checking standard deviation. There's no way to know if a seed was dropped there or not, unless you find some evidence that a plant or seed once existed there.
With all this said it's not time to take it easy and back off maintenance or run faster and kick up the error factor on stands. Instead, agronomists suggest following the same practices that have helped improve planting performance. After all, seed has never been more expensive. That may be another factor motivating people to take full advantage of every seed that they plant.
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Tagged: farm, planter, insecticides
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