On May 5, 2014, we planted seven different corn varieties at our Agronology 10 Research Center. All varieties came from the same seed company.
I am limiting my remarks, at this time, to the five corn varieties planted on ground where soybean were the previous crop in 2013.
Observations
What I am finding is a 15% plant population difference, about 6000 plants/a—between the best and worst corn stands—all planted on the same day.
With this large variation in this year’s corn stands, I would advise you to check on your emerged population—now!
Determining plant population per acre
To determine your plant population/a, measure several locations throughout your field at the following distances and multiply the average by 1000.
Row Width (inches) Measurement for .001 A
30 17.424 ft. (17 ft. 5 in.)
20 26.135 ft. (26 ft. 2 in.)
15 34.848 ft. (34 ft. 10 in.)