In the Shop
As a farm machinery mechanic and writer, Dan brings a hands-on approach that only a pro can muster. Along with his In the Shop blog, Dan writes a column by the same name as well as the Shop Series for Farm Journal magazine. Always providing practical information, he is a master at tackling technical topics and making them easy for all of our readers to understand. He and his wife, Becky, live near Bouton, Iowa.
In The Shop: Seed Tube Sensor Sensitivity
Apr 24, 2011
I've learned there is a significant difference in sensitivity about seed monitors. I'm not talking about how well seed sensors monitor seeding rate and accuracy--I'm talking about the attitudes farmers have toward what their seed monitors tell them.
Some farmers state, "All I want to know is that seeds are falling through the tubes." They're indifferent about seed spacing, seed population or other variables. As long as the little lights or digitized numbers tell them seeds are going in the ground, they're happy.
Other farmers literally stop planting if the seeding rate or total population varies by more than 500 seeds per acre. They frantically dig and measure and re-calibrate, and often spend the first day of planting within 100 yards of their first pass through the field.
I can work with either type of customer. I may wince when working with the minimalists because I know they're reducing yield potential by not optimizing seed spacing, seed depth, and other critical elements. And I'll definitely cringe when a perfectionist hyperventilates because one row of his 24-row planter shows 200 seeds/acre lower than the rest on a windy, dusty day because I know the inconsistency is due to the strong tailwind blowing dust up seed tubes or messing with the way seeds fall through the tube. (Yes, strong tail winds CAN cause erratic readings on seed monitors.)
The perfectionist is more challenging to work with but I get satisfaction from tweaking his seed monitor system and planter to work to his high standards. The key is to understand the source of any inaccuracies. The aforementioned tail winds can cause the monitor to show erratic under-population even though the planter is dropping seeds accurately. Dirty seed tube sensors also can contribute to apparent under-population. Mis-calibrated radar guns can feed inaccurate mph readings to seed monitors, which cause seed population-per-acre to read high or low even though the planter is planting accurately.
Other under- or over-population readings on seed monitors are accurate reports of planter malfunctions. Failed bearings on driveshafts or in seed transmissions cause under-seeding. Damaged finger units thwart accurate seed delivery. Vacuum delivery systems set too high or too low cause under- or over-seeding.
All of those inaccuracies can be dealt with, as long as the operator knows what rate the planter is actually planting. The only way to know that is to get out of the tractor cab and dig. Dig, dig, and dig some more. Dig behind the planter, count the actual seeds per foot, measure the distance between seeds, and do it in multiple places on multiple rows. Once the operator knows whether or not the planter is planting accurately he can diagnose and fix the problem, whether it is in the planter or in the seed monitoring system. No use blaming the planter if the monitor is inaccurate. No use blaming the monitor if the planter is the problem.
Or, you can take the attitude that as long as seeds are going in the ground, you're "planting." Whatever makes the customer happy makes me happy.