Corn growers are constantly looking for ways to maximize profit. 

Planter condition is one of the most controllable variables that influence profitability.  

Research studies have shown that planter maintenance impacts the quality of stand establishment. 

In 2000, Doerge and Hall conducted a study which showed an average yield improvement of 4.2 bushels per acre due to planter calibration. At some locations, the advantage for calibration exceeded 20 bu/acre.

A research study conducted at Purdue showed yield losses in the range of 7 to 15 bushels per acre were observed in uneven stands.2

One way for corn growers to potentially increase yields with minimal input costs is by improving within-row plant spacing uniformity. Proper planter maintenance, adjustment, and speed result in optimal seed placement. 

Replacement of worn-out parts e.g. finger sets, brushes, backing plates, disks, coulters, etc., and the calibration of planter units play a major role in maintaining consistent seed placement and depth which impact spacing between plants.

Uniform stands reduce competition between plants and take advantage of sunlight to maximize yields.

Fine tuning planter seed meters will position producers to grow uniform stands that will maximize profits. The yield increase needed to just offset the cost of planter meter calibration for a 600-acre corn grower using a 12-row planter is only 0.5 bushel per acre (Doerge and Hall, 2000). 

Table 1 shows that recalibration management decision is valid over a range of corn prices and calibration costs.  Industry representatives recommend that planter units be recalibrated every 75-100 acres/row unit or every three years.

Table 1.  Increased Yield Required to Cover Recalibration

 

Cost of Recalibration per Unit

 

$60

$90

$120

$150

$180

Corn Value

Increased Yield Needed to Cover Costs

$/Bu.

Bushels

$3.00

0.20

0.30

0.40

0.50

0.60

$4.00

0.15

0.23

0.30

0.38

0.45

$5.00

0.12

0.18

0.24

0.30

0.36

$6.00

0.10

0.15

0.20

0.25

0.30

$7.00

0.09

0.13

0.17

0.21

0.26

 

1Doerge, T.A. and T.E. Hall.  2000.  The value of planter calibration using the MeterMax system.  Crop Insights 10(23):1-4, Pioneer Hi-Bred International, Inc., Johnston, IA.

2Nielsen, R.L.  1997.  Stand establishment variability in corn.  AGRY-91-1 (rev. 1997), Department of Agronomy, Purdue University, West Lafayette, IN.

The farm level impact on profitability can be quite significant.  A producer who plants 300 acres of corn each year with a six row planter should calibrate his planter every two years.  The following example shows the benefits of recalibrating a corn planter.  

Assumptions for this example are:

•             6 row planter

•             300 acres corn planted

•             Recalibration cost $35/unit

•             Replacement parts $85/unit

•             Corn price $5.50/bu

•             Increased yield due to unit recalibration 4 bu/acre

Revenue

 

($5.50/bu X 4 bu/acre increased yield) * 300 acres =

$6,600

Expense

 

(Calibration $35/unit + repairs $85/unit) * 6 units =

<$720>

Net Profit

$5,880

Non-uniformity in corn stands places a grower’s sizable investment in their planter, seed and other inputs at risk of lower returns.

Many times producers forget the impact that skips (missing plants), doubles, triples, and inconsistent plant spacing have on reducing corn yields.

Replacement of worn-out parts and recalibration of planter units is an easy way to minimize production risk and maximize yields and profits. 

Best wishes for a safe and profitable 2012!