Over the years we have tried to apply the same yield enhancements for corn direct to soybeans with very mixed results. A few years ago, as we pushed the envelope on soybean yields, we did some trials with in-furrow row starter on soybeans. Today, though, we are applying row starter on about 15,000 acres of soybeans as part of a high yield system with very positive results. Not to say we didn’t stub our toe along the way, and I would like to share some of our experiences that got us to where we are today with this program.

Initially, we selected a row starter developed for corn that contained a 50/50 ortho/poly phosphate product with a 10-20-05 and a low salt index. We used this in in-company trials on soybeans on a lark just to empty the tanks on the planter. The visual response was intriguing, so we ran a few trials and recorded data that showed a positive yield response. In 2011 customers installed the equipment on their planters with 15” row splitters, which is common in southern Illinois. This became the base from which growers moved forward on a high yield program for their soybeans, in addition to doing foliar nutrition and stress mitigation applications to maximize genetic potential.

There have been, however, a few bumps along the way. We first learned that soybeans are very susceptible to the salt in the row starter damaging the seed and reducing germination. After reducing stands by as much as 50 percent in plots we realized you must treat seed with a good seed treatment with some type of seed coating included. We used both polymers and soybean oil as a plantability aid with no differences observed between the two.

Next we tried to find the optimum rate (gallonage) per acre. We found that if we go over 3 gallons per acre in 15” rows or 1.5 gallons in 30 inch rows in dry soil conditions we reduce germination. It seems that more starter can cause the seed to swell and break the seed coat and in dry soil conditions there isn’t enough moisture to continue the process and the seed dies.

We also found that, with the 50/50 ortho/poly blend, our product viscosity was too thick to get  even application at that low rate. We decided that adding starter on 30” rows simply won’t work, which isn’t a big deal since more growers plant in 15”rows. But even growers planting in 15” rows were running into issues of even flow with one hose feeding two rows.

In 2014 our supplier made a 100 percent orthophosphate product to use exclusively on soybeans. It was a much less viscus product and flowed better with less resistance inside the flow lines. We also changed the analysis to a 9-18-4 and added Avail to keep phosphate available. This reformulation enabled us to cut the salt index by about 25 percent and improved seed safety for the beans. This move has fixed our flow issues and improved uniformity of application. For 2015 this is the only product we have in inventory and it works equally well on corn and soybeans.

While soybean row starter is still a work in progress, we have learned much from our trial and errors and have been fortunate to have growers willing to ride the “bleeding edge” as we attempt to push their yields up. While row starter is a useful tool in a total high yield soybean system, it does take more management to get an application done correctly and there are no shortcuts to making it work. I am probably most excited about it as a delivery system for micro nutrients, biologicals and fungicides but that is a topic for another article.

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About the Author: Mike Wilson