b'Narrow Rows, Better Yields? The latest research and reflections from academics and seed companies on narrower row spacing, planting density and more.Treena Hein treenahein@outlook.comWHETHER TO PLANTcorn, soybeans and other rowIt adds up to a yield boost of 10 to 15 bushels per acre in crops in narrower rows: Its a question we definitely keepour research, and the seed firms Ive talked to agree with this, getting, says Jason Gahimer, practical farm research operationshe notes. I suspect that 15-inch would be similar, and youd be manager at Indiana-based Becks Hybrids. able to manage even higher densities. Lets say a farmer plants During the past few years, Becks has compared 15-, 20- and38,000 plants per acre in 30-inch rows, with each plant 5.5 30-inch rows in corn across multiple U.S. states, but has noinches apart, which is the minimum needed. In a 20-inch row, definitive conclusions at this point.you get 5.5-inch spacing at a planting rate of 56,000. Our results vary year to year, and in the same year, fromBelow says the average corn planting density across the location to location, Gahimer says. We actually believe whenUnited States is about 32,000 plants per acre right now, and that farmers have different soil types and farm locations, all three fac- this increases by about 400 plants every year. torspopulation, row spacing and hybridsshould be changed,While Below believes narrower rows are a way to achieve but the biggest benefit may be in narrower spacing.substantially higher corn planting rates, he cautions: Its not To better investigate, Becks created a planter in 2018 ena- a trivial investment. You need a different planter and combine bling them to change row width, hybrids and seeding rate. Usinghead too. And secondly, which is a related serious barrier, the this machine in Central Indiana, the firm found that 10-inchresale value of a 20-inch planter is much less than a 30-inch, so rows provided the best yields in silt loam soil with more organicfarmers would lose money when it came to trade-in value.matter. However, in more heavy clay soil with less organic matter,Because of this, Below expects itll be about 10 years before 30-inch performed best. In all cases, the optimal planting ratethe percentage of corn farmers using 20-inch rows increases. was under 40,000 plants per acre, but Gahimer says moreI think it will be exponential at that point, he says. If grain research on all factors is needed.prices were higher, youd see it move quicker. I think itll take Taking a less approached view is Fred Below of the Universitysome farmer-leaders to do it, to show farmers that its working of Illinois, who firmly believes corns future lies in narrower rows.for another farmer over thousands of acres. Farmers generally This professor of plant physiology and his team of graduate stu- feel research by seed companies is to some extent biased, that dents have trialed corn in 20-inch rows for six years all over theresearch by academics is somewhat convincing, but what other state, finding a yield advantage over 30-inch rows.farmers are getting has by far the most influence.No-till corn in 15-inch rows with standing populations up to 59,000 plants per acre in Kentucky research plots.64/ SEEDWORLD.COMDECEMBER 2019'