Laboratory and field testing of seed spacing uniformity for sugarbeet planters

Five planter configurations were evaluated for seed spacing uniformity at three field speeds using a seed location method in the field, and a laboratory method involving an opto-electronic sensor system. Planter performance was described using the Coefficient of Precision (CP3) measure. Results showed that planter seed spacing performance results from laboratory testing were generally higher than results from field testing. Two design advantages, a short seed drop with minimal horizontal velocity, allowed the precision planter to space sugarbeets more uniformly than the general purpose planters. The laboratory testing method may be useful to screen out planters with poor seed spacing uniformity. Field tests must be conducted to determine planter seed spacing uniformity in the field.