A one-acre plot of experimental cropland at Iowa State University is being recognized today (Thursday) for being continuously used to grow corn — for more than nine decades. John Pesek, a retired I-S-U agronomy professor, says the plot was first planted with corn in 1915.

Pesek says “Being as a plot of corn that long is relevant because it is an example of what can be done, or cannot be done, growing corn after corn for years on the soil fertility and the yields of the corn crop. There are only three other plots that predate these plots in the United States.”

While the corn field in Ames has been in use for 91 seasons, Pesek has been involved with that same plot for more than 50 years. Over that time, he’s seen some radical changes in crop yields. Pesek says “Oh my gosh. We put the new treatments on in 1953. Before that time, I think the yields leveled off somewhere below 40 bushels per acre. With fertilizers applied and the current hybrids that we use, they bounced up well over 150 bushels within a couple of years.”

This plot is the final remaining plot of six original test plots at I-S-U. Pesek says it served as a “control” plot in many experiments in crop rotation — the practice of planting different crops on the same plots of land year after year to avoid depletion of soil nutrients.

Pesek says “Back when these were established, rotations were absolutely critical and this showed that because the rotation experiment covered 20 or 30 acres, testing five different cropping systems and various fertilizer, lime and manure treatments. Those plots always outyielded the continuous corn plots and there’s an example of how not to grow corn.” Tours of the plot are being offered today (Thursday) starting at 2:30 P.M.