1. February 8, 2013 - Special Edition
Optimizing Soybean Planting Populations in 2013
2012 Weather Conditions & Effects on Seed Quality Handling This Year’s Soybean Seed
High temperatures and drought conditions throughout the A hot dry finish to the 2012 soybean seed crop has resulted in
pod and seed development stages resulted in some seed lots soybeans with lower moisture than historical averages and
with: with thinner seedcoats resulting in fragile soybeans that are
Irregularly shaped seed more easily damaged by handling.
Wrinkled seed coats
Other physical effects Steps to reduce handling damage:
Fragile seed coat Minimize the distance soybeans fall to hard surfaces,
less than 1 foot is most desirable.
These industry-wide problems have resulted in germinations Consider a belt-type conveyor and try to avoid any
that are 5 to 10% lower than normal in some cases. Standard type of auger system
warm germinations for much of the seed will be 85% this year, Reduce handling if possible and minimize box to box
compared to 90% normally. In addition, specific lots of some movements. Avoid rough handling of seed bags and
varieties will be offered at lower germination labels to help large drops.
customers avoid supply shortfalls. Keep seed treaters running near capacity when
treating.
Seeding Rate & Planter Recommendations
To calculate a seeding rate, Use the following equation:
EXAMPLE:
Seeding Rate = Seeding Rate for a 150,000 desired plant population=
Desired Plant Population 150,000
(% Germ) x (% Pure Seed) x (% Live Seed Emergence*) 85% Germ x 98% Pure Seed x 97% emergence
*Normal emergence factor 95-97%, potential = 187,500 seeds per acre planting rate
tough/crusted environments factor 90-92%
Quick view seeding rate adjustment chart below for 30” row spacing assuming normal emergence environment.
Desired Final Stand
Germ %
120,000 130,000 140,000 150,000 160,000 170,000
90%
141,000 152,000 164,000 175,000 187,000 199,000
85%
150,000 161,000 173,000 186,000 198,000 210,000
80%
158,000 171,000 184,000 197,000 210,000 224,000
Summary
Several factors influence seeding rates such as row spacing, seed germination rate and emergence environment.
Utilize seed treatments to minimize additional factors of stand establishment.
Read the seed tag for each bag or unit and make seeding rate adjustments accordingly.
Consult your Pioneer Sales Representative for additional field to field recommendations.