Wheat Seeding Rate Tips and Recommendations
In 2008 and 2009 Gary Prill and I conducted wheat seeding rate trials with the objective to evaluate the yield response of one wheat variety to four different planting populations ranging from 1.2 to 2.1 million seeds per acre.
This studies were set up with four different seeding rates replicated up to six times in a randomized complete block design. The seeding rates used the trials were:
- 1.2 million seeds/acre
- 1.5 million seeds/acre
- 1.8 million seeds/acre
- 2.1 million seeds/acre
For both 2008 and 2009 the studies were planted following the fly-free date for Van Wert County, Ohio (September 26) using a John Deere 750 no-till drill. The drill was calibrated for the proper seed drop for each target seeding rate based on the seeds per pound seed count on the variety. Plot size was 300 feet long in 2009 and 1070 feet long in 2008. Pre-harvest head counts at harvest time were estimated by counting the number of heads in one foot of row at six separate locations within each plot. These counts were converted to heads per acre. Harvest was accomplished with a John Deere combine equipped with a calibrated AgLeader PF3000 yield monitor. For each plot, grain weight was determined with a calibrated weigh wagon. Moistures were taken from the yield monitor average reading for each plot. All yields were adjusted to 13.5% moisture.
Treatment Yield (2009) Yield (2008)
1.2 M seeds/acre 97 93
1.5 M seeds/acre 99 96
1.8 M seeds/acre 99 96
2.1 M seeds/acre 101 97
M = million; yields reported in bushels/acre
There were no statistical differences (P=0.05) among the treatments for moisture, yield, or head count. The head counts taken in this study would indicate that lower seeding rates were able to produce comparable number of heads per acre, and comparable yields to the higher seeding rates. From an economic standpoint, each 300,000 seeds/acre increase in the seeding rate increased seed cost by $6.75 per acre. This is based on the 2009 seed cost of $31.50 for 1,400,000 seeds. This would require an additional 1.7 bushel/acre yield increase to pay for each additional 300,000 seeds planted based on a harvest time market price of $4.00 per bushel for wheat.
According to Ohio State University agronomists, the optimum seeding rate is 1.2 to 1.6 million seeds per acre (18 to 24 seeds per foot of 7.5-inch row) when planting during the two weeks following the fly-safe date. During the third and fourth week after the fly-safe date, the optimumseeded rate is 1.6 to 2.0 million seeds per acre (24 to 30 seeds per foot of row).
Full studies available here-
Full podcast here: