On-farm Trials, Increasing Populations with Twinned Rows in Ohio Watters, H.D., Foster, S.S., Kleinschmidt, A.W., Prill, G.L., Yost, J.K. The Ohio State University Extension ON-FARM TRIALS, INCREASING CORN POPULATIONS WITH TWINNED ROWS IN OHIO Watters*, H.D. , Foster, S.S. , Kleinschmidt, A.W. , Prill, G.L. , Yost, J.K. * presenting author In the mid-1990s many were trying to increase yield and populations in hybrid corn with narrow rows, mostly using 15-inch row widths. But that required a specialized head to harvest the crop. In our trials we used twinned rows of corn 7.5 inches apart on 30-inch centers to create narrow rows but were able to use a 30-inch corn head for harvest. Seven on-farm yield trials were conducted over four years (2003 to 2006) comparing twinned rows on 30-inch centers to conventional 30-inch rows in western Ohio at three sites, in Darke County (west central Ohio), in Van Wert County (northwest Ohio) and in Fayette County (southwest Ohio). We used the Great Plains Precision Plant drill to plant the twinned rows and a conventional planter to plant in 30-inch rows. Various hybrids were used, and at one site (Darke County) they were chosen based on predicted adaptability to narrow rows. Seeding rates from 30,000 up to 50,000 seeds per acre were used in both twin and 30-inch rows. In general we did see a slight yield boost by increasing the seeding rate to 35,000 to 37,000 seeds per acre, but we also observed this in 30-inch rows for increased populations. Growing corn with the Precision Plant drill did not reduce yield, even when planting in 30-inch row widths. The drill may be an excellent choice for a producer needing a multi-purpose planter for wheat, soybeans or corn. Abstract: Twin rows early season Canopy closure twin rows vs. 30 inch Photos courtesy of Steve Foster. In 2003 we saw the results we expected. In the 30 inch rows yield was similar across seeding rates. And in the twin rows yield increased as we increased our seeding rate to higher levels. With more room to grow without crowding, yield was increased. We also saw the hybrid interaction we expected in 2003. While the hybrids performed similarly in 30-inch rows in twin rows the short, fixed ear hybrid (P34G13) performed much better than the older, tall, flex ear hybrid (P33Y18). Random differences? Some have said that a “drill” cannot plant corn. So in 2004 we compared the Precision Planter to a John Deere no-till planter, and achieved the same results for both in 30-inch rows. We all pushed the seeding rates, this shows the plateau we usually saw. You can push seeding rates to 35-37k, but once in the 40s – whether twin row or not – yields do not increase. Row planting unit Great Plains – GP 1510 Precision Seeding System w/ CPH15 No-till Hitch Seed singulation mechanism Pictures from Great Plains http://www.greatplainsmfg.com/