Four steps to boosting your soybean yield
The first thing to know about maximizing soybean yields is that the two biggest profit makers are planting date and row spacing. That probably doesn't surprise many farmers. But there are a few facts to keep in mind in thinking about how to increase yields and profits.
Ohio State University Extension agronomist Jim Beuerlein shared the following facts in a recent edition of the C.O.R.N. Newsletter:
Yield potential starts to decrease in early May most years and by late May is just over a half bushel per acre per day.
A five day delay in planting the last week of May will reduce income by $30 per acre if soybean is worth $10 per bushel.
Switching to narrow rows will also increase yield and profit. On light colored soil, the row spacing should be as narrow as possible regardless of planting date. On dark colored soil, row spacings should no wider than 15 inches in May and as narrow as possible for June plantings. Yield increases about one-third bushel per acre as the row spacing is decreased from 30 inches to 7 inches.
What if you are already planting early in narrow rows? Beuerlein says there are two other very profitable practices: fungicide seed treatments and inoculation.
Fungicide seed treatments will ward off infection of the root rot diseases for two to three weeks allowing plants to get a head start on diseases and be better able to ward off the yield loss caused by disease.
He says that over time, the use of fungicide seed treatments in Ohio will increase yield three to eight bushels per acre depending on soil drainage, crop rotation, variety selection, and other factors.
The results of a 2003 fungicide seed treatment study Beuerlein conducted in Ohio are available here:
He says the take home message from the study is that fungicide seed treatments are very effective tools for improving plant stands and root system health. "Seed treatment fungicides should always be used on soybeans, regardless of variety, crop rotation, soil type, planting date, or tillage," he says.
As for inoculation, he says most producers can expect yield increases of three to eight bushels per acre depending on soil characteristics and yield potential. Results of Beuerlein's 2004 Ohio Soybean Inoculation Study are available here:
He says ten years of soybean inoculation evaluation consisting of 66 field trials and over 7000 research plots indicate that inoculating soybeans is a very profitable practice. The average yield increase over ten years has returned a profit of over 300 percent. For most inoculation products, a yield increase of half a bushel per acre is profitable and yield increases of 2 to 7 bu/acre have been common. Since 1995 the inoculation of soybean seed in Ohio has increased from a few thousand acres to over two million acres. The primary reason for the rapid increase in use of inoculation materials is that over time their use has been profitable.
When applying a fungicide or using fungicide treated seed, be sure the fungicide has dried before applying inoculation material to the seed. Inoculation products may be mixed with some fungicides and applied to the seed together. Be sure to check labels for compatibility. Work is underway to develop formulations of fungicides that can be premixed with inoculation materials and applied together.