Did smoke help the 2023 corn crop?
Assistant Professor of Corn Production at Purdue University’s College of Agriculture, Daniel Quinn, PhD. recently provided fascinating insights into the impacts of fire on major corn producing areas, many of which have been impacted by smoke from wildfires.
Quinn was the keynote speaker at the 2024 Great Ontario Yield Tour Event in Woodstock Ontario on August 29, 2024.
In recent years both Canada and the United States have experienced an increase in air quality concerns during the summer due to elevated incidence and severity of wildfires in the western U.S and Canada.
In late-June of 2023, air quality warnings were issued throughout the Midwest and Canada due to smoke caused by severe and widespread wildfires, which resulted in a noticeable haze and reduction in direct sunlight. So, the question asked by many farmers is how does smoke impact crop development?
Quinn highlighted the complexity of the situation, explaining that the impact of smoke on crops varies in both negative and positive ways, influencing the photosynthesis process and potentially altering yield outcomes.
The dialogue was not only educational but also timely, considering the increasing frequency of wildfires and their broadening impact on agriculture.
Quinn explained that in years where we see higher temperatures and lower precipitation, we are seeing greater wildfires – which makes sense.
The recent 2023 fires showed the black smoke – which blocks out sunlight – over many high production areas.
Quinn shared a slide which asked if the smoke conditions negatively impacted Midwest corn production, and his answer brought laughter to the group, “Yes and no, it’s complicated,” he said with a smile on his face.
The smoke, of course, reduces sunlight because the smoke reflects sunlight. Plants need sunlight to photosynthesis. Smoke also increases ground level ozone, negatively impacting air quality warnings for humans, but it also has a negative impact on plants.
Quinn explained that the timing and intensity of solar radiation reductions is important. Is it during silking to maturity? after emergence?
He also highlighted that wildfire smoke can positively impact corn by diffusing photosynthetically active radiation by scattering the light, helping the light better penetrate the leaf canopy in corn.
Quinn believes the smoke may have helped with the 2023 corn crop, which was dry and hot in June. The smoke reduced the temperature and reduced the plant transpiration – reducing water loss. But the timing of when that happened was important.
Quinn also reviewed factors related to heat stress.
Watch the video below to see Daniel Quinn’s complete presentation and learn all of the complicated details.