Prescriptions

Monday, March 4, 2013

I’ll be calling our Monsanto seed dealer, neighbor Jeff Jackson to learn if he has some seed sizes for our soybean seed.  We need to know that particular number, the seeds per pound, in order to write the planting prescriptions.  That number is different for each variety.  The soybean planter regulates the planting rates by measuring pounds of seed per acre… therefore, we must know how many seeds are in each pound in order to reach our target planting population…which is based on seeds per acre.  An average rate for us is 170,000 bean seeds per acre.

Determining the planting population for soybeans is counter-intuitive.  On better or more productive soils, we actually decrease the population, and for thinner or less productive soils, the rate is increased.  Using this variable-rate, soil-specific planting technique, it has allowed us to decrease our overall seed costs per acre by 10%– compared to planting a single-rate population across all acres.  With our soybean seed costs over $55/acre, such a system provides significant savings!

Brandon will assist me in writing the prescriptions this spring, and in so doing, he will learn the ‘how’ and ‘why’ of matching planting populations to soil types.  Upon examining a soil survey, we learn the productivity potential of each soil type…. and in our fields, we have from one to nine different soil types– most have 4 or 5.  From our experience, we can assign a planting rate to each soil type, typically in a low, medium, or high population rate.  In the John Deere Apex information management program, we build a prescription map, overlaying the appropriate population number on each soil type in the map.  This creates a new prescription map that shows the low, medium, and high rates.

This is a map of the soil types for a fleld here at the home farm.  You can see how many different types exist in just one field.

This is a map of the soil types for a fleld here at the home farm.  You can see how many different soils exist in just one field–this one has 9!

Here is a planting prescription designed for this same fleld.  Notice the red, yellow, and green colors correspond to low, medium, and high population rates.

Here is a planting prescription designed for this same fleld. Notice the red, yellow, and green colors correspond to low, medium, and high population rates.

Subsequently, as the soybean planter passes over the field, the GPS system reads the prescription map and automatically adjusts the planting rate of the seed to match the productivity potential of the soil.  And all the while, saving us 10% of overall seed costs!

Writing a prescription for each soybean variety for each field becomes a bit tedious or cumbersome, but the results are beneficial.  It’s so worth the effort.

In meeting with the Operations Manager at the John Deere Seeding Group in Valley City, ND during our tour last week, I requested the following improvements to their system.  1.  A seed metering system that actually counts the seeds/acre rather than calibrated on pounds/acre.  This would allow me to write one master prescription for each field, and it would probably be good for multi-year use.  2.  A section-control system on the metering system so that overlapping planting would not occur when in point-row situations.  They tell me these are under development!  Maybe by the time I order the next drill in 3-4 years, these features will be available.

Congratulations to the Purdue Boilermakers on yesterday’s win at Wisconsin.  It is a rare thing for any visiting team to win in the Kohl Center, but oh, how sweet.  In this year with modest success, such a win is a treasure.  Maybe this win will help them get into the NIT.

Ben has reminded me that Purdue is the only team with a winning record (10-8) against the Badgers with Bo Ryan as their coach…and the only visiting team with 3 wins in Kohl Center.  So, maybe the win wasn’t as unexpected as some may have thought!

This entry was posted in Farm Days, News, Planting and tagged , , , , , . Bookmark the permalink.

2 Responses to Prescriptions

  1. casifarm says:

    Reblogged this on Carnahan & Sons, Inc. and commented:

    This task is coming soon to Carnahan & Sons…

  2. Pingback: On the road again | Carnahan & Sons, Inc.

Leave a Reply