1. Variable Rate Seeding Technologies
Presented by Matthew Steinert

2. Objective
Explain some of the methods and procedures currently in practice
Highlight variable rate seeding equipment that is currently available
Discuss the future of variable rate seeding

3. What is Variable Rate Seeding?
Obtaining the optimum seeding rate needed for each area of the field to achieve maximum profitability.
Planting the optimum variety for each area of a field to obtain maximum economic return.
Also includes the application of any fertilizers or other crop inputs applied at planting.

4. Basis for Variable Rate Seeding
All areas of a field are not capable of producing the same germination rate nor of supporting the same final plant population.
PortA
Misclassified
KirklandB
KirklandB2
NorgeC2
NorgeB
-Soil Type
-Moisture Availability
- Fertility
-Field Traffic Patterns
-Field Topography
Solie, Remote Sensing, available at soil4213.okstate.edu

5. Variety Selection
-Plant variety that will yield best on each soil type within the field.
-plant high yielding variety on Sandy Loam soil
-plant lower yielding saline tolerant variety on saline soil
-plant more drought tolerant varieties on thinner sandier soils with less water holding capacity
Reinach Very Fine Sandy Loam
Dale Silt Loam - SALINE
Solie, Remote Sensing, available at soil4213.okstate.edu

6. Basis for Variable Rate Seeding
-Field element size for variable rate seeding can be larger (30m^2)
-most grain crops are able to moderately compensate for high and low plant populations to achieve maximum yield.
-topographical features change more gradually in a field than fertility
-properties related to soil type also change slowly across the field (pH, water holding capacity, soil texture)

7. Current Practices
Most research has been in corn and other high value crops
Currently same plant population seems to be best for a range of yield goals
Best strategy may be to adjust seeding rate to achieve uniform final population
Rates may be adjusted if extreme differences in yield potential exist within a field
Changing rates as well as varieties using management zones appears to be most promising strategy
Increasing seeding rates in areas with historic weed problems to achieve canopy sooner
Corn Grain Yield Level (bu/acre)
Recommended Harvest Populations (plants/acre)
>180
30.000
180
26,000-30,000
160
140
120
100
22,000
<100
18,000
“Crop Insights” PHI , 1999

8. Flexi-coil Variable Rate planter with nurse system
Equipment: Air Drills
Flexi-coil Variable Rate planter with nurse system
Flexi-coil Variable Rate Air Drill

9. Product Metering
Fluted Meter is very accurate and can be calibrated for most any product or variety.
Meter is driven by hydraulic torque drives in tandem with electric motors for rapid adjustment and precise control.
Up to three products can be applied simultaneously at different rates and applied to separate locations in the soil.

10. Variable Rate Metering
Monitor allows for infinite rate adjustment either manually or automatically from prescription maps
Fully GPS compatible with ability to display GPS data as well as create as-applied map
Automation is advantageous due to operator fatigue and other factors related to human error

11. Variable Rate Planters
Ability to control each planter section of 4-6 row independently. (Tractor hydraulic flow limiting factor to smaller control units)
Ability to vary fertilizer rate simultaneously
Coming soon: ability to switch varieties on the go

12. Conventional Seeding Equipment
Variable rate grain drills non-existent
Conventional planters are expensive to modify and have limited potential
Air systems have extreme versatility
-ability to plant almost any crop
-same cart can be used to seed small grains, nurse
planter, or band and broadcast fertilizer
Air systems are economically advantageous even when variable rate ability is not taken into consideration

13. The Economic Benefit
Currently the largest economic benefit of variable rate seeding appears to be from varying rates of fertilizer applied simultaneously
Phosphate is most common nutrient applied in conjunction with seeding operation
If one time P2O5 sufficiency index’s could be established for areas of the field by either analysis of historical Landsat imagery or from response index’s obtained from foliar phosphate application using remote sensing then variable rate phosphate application could be made based upon removal calculated using Landsat or yield monitor data.
Current ongoing studies in their fifth years on farms in both North Dakota and Saskatchewan show economic benefits from these practices

14. ?Your Questions?