For most growers, the success of a season is determined with the combine passes that tell us final yield. While this measurement has the most direct and tangible impact to a operation’s bottom line, how does each grower decide throughout the growing season if they are “on track” for their yield expectation or whether other measures should be taken? Most of us have important times during the growing season to assess the crop which most often occur at emergence where we assess stand establishment signifying a strong start and during or immediately after pollination to determine yield potential for the remainder of the year. These are key milestones, but another that seems to garner less attention is crop canopy.
We know that greater leaf area and/or plant mass give the plant the opportunity to absorb more sunlight to gather photosynthetic products. We know that growing season sunlight is finite across a field each year. It’s also important to understand that gathering more photosynthate earlier will not only increase yield, but also provide other benefits from establishing a uniform canopy earlier in the growing season.
Corn, like most plants, utilizes 70%-80% of the water accessed for cooling of the plant architecture, like the way you or I would sweat to cool off. While this process is like evaporation, it is referred to evapotranspiration. One of the main objectives for a growing season is to pass as much available moisture from the soil to the plant instead of losing moisture to evaporation.
To guard against evaporation, a distinct effort should be placed on reducing the time of sunlight penetration through the canopy which will ultimately reduce heating of the soil surface – especially on acres that are prone to water limitations through the growing season. The goal is to capture as much of the rainfall received because moisture limitations on some acres will arise at some point.
Rain in the month of May, while sometimes plentiful, should be thought of as a resource not only to “build the plant” and supply nutrients but also to cool the plant for days to come. Increased plant temperature (>86°F for corn) even during the mid to late vegetative stages “burns off” the carbohydrates, captured through photosynthesis. The increased use of reserve carbohydrate limits the total carbohydrate available to support yield during the grain filling period thus reducing yield potential.
Efficient use of soil moisture (improving plant growth and development, increasing soil nutrient accessibility, and enhancing overall plant health) that is why we are on a “race to canopy”. We’ll explain more about how you can manage the race to canopy in our next blog posts around planting considerations and fertilizer planning.
The team of agronomy and data experts at Advanced Agrilytics provides an unbiased view of agronomic opportunities and challenges across their customers’ operations. Find your local Precision Agronomist here or by emailing firstname.lastname@example.org.
Dr. Kess Berg
Chief Technology Officer & Advanced Agrilytics Co-Founder