Have a Merry Corn School Christmas

Uniform cobs, 2022 Photo Credit: Mark Sultenfuss

The Christmas holidays are here! What better way to spend the time than catching some of the 30 Corn School episodes RealAgriculture published in 2022?

We kicked off the season in January with Purdue University agronomy professor Dr. Tony Vyn who tackled the question: where does yield come from? Vyn notes that hybrid research over the past 30 years suggests that two-thirds of the yield increase growers are now experiencing can be attributed to higher kernel weights, when hybrids are compared at optimum plant density. He adds that one-third of yield increases result from higher kernel numbers.

One of our more popular episodes of 2022 featured a short tutorial on how to zero the planter for even emergence. In this video, Kearney Planters sales and customer care specialist Jay Curtis shows why zeroing row units is important and how to do it before planting.

With the arrival of warmer spring weather, we headed to the field for some planting tips with PRIDE Seeds agronomist Matt Chapple. On this episode, Chapple demonstrates why it’s important to plant when the soil is fit and what can happen to impatient planters later in the spring and throughout the growing season.

In early June we looked at root development from planting to emergence with PRIDE Seeds agronomist Sara Meidlinger. She notes that even before the crop has emerged, growers can still do some diagnostics to evaluate how everything is going and get a better understanding of the corn root, and how the corn plant is growing.

Back in Ontario, we caught up with BASF technical development manager Rob Miller to highlight three weed control crop staging methods growers can use to determine whether the crop is in the correct development stage to apply post-emergent herbicides. Miller says a product like glyphosate can be applied all the way up to the 8-leaf stage. But other herbicides have tighter timing and need to be sprayed in-crop at the 4 or 5-leaf stage or at 7 or 8 leaves, for example.

Next up we have AGRIS Co-operative agronomist Dale Cowan on how retailers and researchers are field testing biostimulant products to better understand how, where and when they can deliver value to growers. Cowan says growers can expect to see more and more biostimulants as manufacturers look to bring to market management solutions that alleviate the abiotic stresses plants experience when growing conditions are either too hot, cold, wet or dry.

Check out all 2022 Corn School episodes

Managing nitrogen was a huge focus for growers in 2022 as the price of the nutrient skyrocketed due to geopolitical events. How much fertilizer do farmers lose when they apply nitrogen in season? Is volatilization a significant problem? Could 4R nutrient management and urease inhibitors help? University of Guelph researcher Josh Nasielski addressed all these questions in this August episode. He shares what he and his collaborators are learning about the best way to minimize in-season losses using a 4R nutrient management framework — right source, rate, time and place.

Protecting yield potential from northern corn leaf blight and a newer pest, tar spot, requires being well-armed and ready to apply the right fungicides at the right time. That’s because these diseases are not only big yield robbers, but the window to provide adequate control is quite narrow, and gets narrower with certain weather conditions. On this episode, BASF agronomist Ken Currah talks corn fungicide fundamentals, including tassel timing, DON suppression options, and the stay-green effect.

Soil, water and topography maps — more commonly know as SWAT Maps — are becoming a familiar management tool for corn producers.

These high-resolution soil foundation maps are used to execute variable rate fertilizer, seed, soil amendment and pesticide applications. On this episode, Corn School host Bernard Tobin catches up with Sullivan Agro’s Paul Sullivan as he is putting SWAT Maps to work in one of his clients’ fields. In the video, Sullivan describes how he used SWAT Maps to identify 10 unique production zones within the Arnprior, Ont. field and how variable rate planting and nitrogen scripts have been developed and applied to optimize production in each zone.

To wrap up the 2022 Corn School season, we visited with Ontario Ministry of Agriculture, Food and Rural Affairs plant pathologist Albert Tenuta at his tar spot research nursery in Rodney, Ont. Fungicides are a key tool in the tar spot management toolbox. But what’s the best time for growers to apply a fungicide to get optimal control of the disease and the best return on their crop protection investment?

Tenuta and other pathologists from across North America have been working to evaluate tar spot fungicides, and application timings. It looks like a double application — when fungicide is applied at the VT/RI stage and again three weeks later at R3 — may be the best control option. But will it pay for growers to double apply fungicide to control tar spot? Does it deliver higher yields and a return on investment?  Stay tuned for more insights when the RealAgriculture Corn School returns in 2023.