Time to Evaluate Soybean Stands

Uneven Soybean Emergence

The soybean agronomy team is busy travelling across the state conducting stand counts on our field trials. Target stand and actual stand can vary considerably depending on planter calibration (or lack there-of), environmental conditions (i.e., soil moisture, crusting, etc), and disease/insects.

To quickly estimate soybean stand, count the number of plants in 1/1000th of an acre in several areas of the field. Roughly, this corresponds to the number of plants in 70 foot of row for 7.5 inch row spacing, 35 foot of row for 15 inch row spacing, and 17.5 foot of row for 30 inch row spacing. 

Last year, with funding from the Ohio Soybean Council, we conducted a seeding rate study at three locations.  (At all three locations, soybeans were planted in May.) On average, harvest populations of at least 100,000 plants per acre resulted in 90% relative yield (individual plot yield divided by highest yielding plot within a location). Keep in mind, this is based on harvest population (of a relatively even stand) and actual seeding rate should be greater to achieve at least 100,000 plants/acre at harvest. In our soybean trials, the target seeding rate is 150,000 seeds/acre (in 15-inch row width) which usually results in 109,000-136,000 plants/acre at harvest.

Author(s):

About the C.O.R.N. Newsletter

C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.