Wrong Move On Soybean Replant Decision Can Cost You Dollars

Existing population is where any replant decision starts. You can determine the existing population using methods and charts described in the Purdue University Corn & Soybean Field Guide.  Knowing that soybeans compensate much more than corn for thin stands by branching, and understanding the importance of planting date, are also factors. Here are more things to consider when deciding what to do with that stand of soybeans that just isn't up to your standards.

No guarantees second time around- One farmer several years ago wanted a good stand in front of a perspective landowner's house who had ground to rent the next year, so he replanted that 5-acre section three times. Every time a big rain fell within 24 hours of planting. That was the days of conventional tillage and the soil crusted easily. The last planting date was June 14, and the stand was no better than the first time, planted May 15. It was clearly a losing proposition.

Patching in may affect harvest- Depending upon how late you decide to tear up patches within the field and replant, leaving the rest, you may encounter varying maturity at harvest. That can complicate combining.

Soybeans maturity is controlled mostly by day length, not temperature, but temperature will have some affect. The other option might be to plant an earlier variety.

No-tilling in more seed seldom works- Some have tried going into thin stands and no-tilling in more seed next to the plants already established. Farmer testimonials say that seldom raises yield. Shaun Casteel's recent revelations that later-emerging soybeans contribute little or nothing to yield, depending upon when they emerge, probably explains why this practice isn't as effective as it might seem it should be. Casteel is a Purdue University Extension agronomist.