Evaluating corn planter performance
Jun 11Evaluating corn planter performance
There are three key factors to investigate when evaluating your planting and planter performance; final populations, uniformity of spacing and uniformity of emergence.
Final populations can be calculated in 30 inch rows by measuring 17’5” and counting the number of plants in that distance and then multiplying by 1000 to get the number of plants/acre. If your number is not within 5-10% of your seed drop, you will want to adjust your planter.
To evaluate your uniformity of spacing, look for doubles and skips when walking your fields. The table below shows you how many inches should be between seeds at different seeding rates. Research is split on how spacing affects yields. Some studies show that every additional inch between seeds could cause a loss in yield of up to 2.5 bu/acre. Research conducted here in Ontario by Tony Vyn and Greg Stewart, showed that plant spacing uniformity had very little effect on final yields. If your target population is reached, plant spacing will likely have a very small influence on yield. Factors leading to poor in-row spacing are poor planter maintenance and fast planting speeds.
Looking at leaf stages across your field will allow you to determine uniformity of emergence. Plants that emerge late (1- 2 leaves behind), will see a yield loss. Planting at a uniform depth and into uniform soil conditions are critical for achieving uniform emergence. A study conducted by the University of Guelph demonstrated that if 1 in 6 plants suffered a 2-leaf delay, the overall yield reduction was 4-5%.
Take a bit of time this summer to take a look at your planter. Check your opener discs (most discs are 15” in diameter, if they are worn down to 14”, it is time to replace them), level the planter, adjust seed-firming wheels, check seed tubes and meters as well as seed depth placement. These actions can significantly increase yields and returns. Talk to your local equipment dealer for more information on planter maintenance.
Laura Johnston, CCA-ON, Maizex Seeds Yield Specialist, West Elgin County