Dust Storms In Illinois: Examining Roles Of Weather And Farming Practices

JENNA BRAASCH

URBANA, ILLINOIS

Recent dust storms in Illinois have raised the question of the cause of these events. In the last few years, these dust events have caused fatal accidents among traveling motorists. Another public concern is the drop in air quality during these storms.

Some of the emerging questions concerning dust storms include:

• Has spring weather become windier, leading to storms that coincide with the period when crop fields are most vulnerable in April and May, before and just after planting?

• When the winds increase over bare or recently planted farm fields, are soil particles now more likely to be picked up and moved by the wind?
• How many deaths occur from dust storms in Illinois?

According to the National Oceanic and Atmospheric Administration in an April 2023 article, dust storm deaths are underreported. NOAA states that 14 to 32 deaths from these storms occur per year across the country. In 2023, eight people were killed in one dust storm on a central Illinois interstate highway.

Factoring In Weather

A recorded review of April wind speeds for Illinois from NOAA shows that 2023 and 2024 were higher than average. Wind speeds in the month of May, however, were lower than the historical average. While, in general, soil moisture has been adequate the past few years, there have been times of below-average soil moisture. According to the Illinois State Water Survey at Prairie Research Institute research tracking, this was the case during the severe dust storm in May 2023. 

“Another factor related to weather is to examine the potential evapotranspiration, which is the amount of moisture that plants and soil can give off if the moisture is available,” says Duane Friend, climate change specialist with University of Illinois Extension. “Current weather research shows that potential evaporation has, in fact, increased in recent years, but most of that evaporation has occurred during the summer, not the spring.” 

Even though it doesn’t appear any trends can explain the recent dust storms, there can still be very localized conditions where surface soil may be dry, and winds may be sufficient on individual days that could cause dust storms to occur. The answer is that weather is not causing widespread dust storms but might be a factor in localized situations.

Factoring in Farming Practices

Dust storms are not new occurrences in Illinois. The Dust Bowl storms of the 1930s quickly come to mind, but dust storms also occurred in the 1960s and 1970s. The storms abated as reduced tillage practices occurred partly due to concerns about erosion and a method to conserve fuel during and after the oil crisis of the 1970s. 

But what has changed? With modern tillage methods, the speed of farming has almost doubled in just a few years. Farmers invested profits into updating farm machinery with high-speed equipment. 

Why has farming speed increased? First, in the late 2010s, the planting season stretched well into June in some years, resulting in lower yields. In some cases, fields could not be planted due to weather conditions. Planting faster allows crops to be planted earlier, resulting in higher overall yields. Technological advances in farm machinery have expanded farm equipment's speed and productivity, leading to more efficient cultivation of more row crop farmland planted in April and May.

Additionally, vertical tillage tools are good at breaking up corn stalks. Vertical tillage lifts and loosens the top area of the soil. However, multiple passes on corn stalks left over from the previous crops leave behind reduced plant residue on the surface, resulting in soil particles becoming airborne. Even with vertical tillage equipment, fall tillage greatly reduces soybean stubble, which can hold soil particles in place. After multiple tillage passes, a loose horizon of topsoil that can easily blow is left behind.

Farmers fall till to increase the odds of getting planted in the spring should rains occur and then till again in the spring before planting. Two and three passes with tillage equipment are not uncommon, each pass reducing the protection of soil particles and reducing topsoil to a powder.  Imagine pouring baby powder into a hand and then blowing on it. What happens is a smaller-scale version of what happens on farm fields. The particles blow away. 

Factoring in Profitability

Are more frequent and intensive tillage practices more profitable? Conservation research has shown profitability decreased or stayed the same with increased tillage passes and intensity of seedbed preparation on corn. According to a 2015-2023 Data Summary Report, The Business Case for Conservation, released by Precision Conservation Management, light tillage had a slight benefit with soybean production but not with more frequent and intensive tillage practices.

Farmers may be reluctant to give up their investment. So, what can be done? “One option is to reduce the number of passes across a field with tillage equipment, including on corn stalks,” says Kevin Brooks, commercial agriculture educator with Illinois Extension.

Second, fall tillage on soybean stubble should be eliminated altogether. This elimination is especially important because research shows no benefit to fall tillage on soybean stubble, both on yield and financial returns. 

While pinpointing the exact causes of recent dust storms may be difficult due to the many factors involved, all can agree on the need to prevent future tragedies. Farmers can consider reducing or eliminating tillage.

For more information, read more in Dust Storms in Illinois: Identifying Farm Solutions or contact a local Extension office.   ∆

JENNA BRAASCH: University of Illinois