By: Michael Lauher
As summer approaches and the temperature climbs higher, the air hums with the energy of the season, with each day bringing warmer temperatures. As we bask in the familiar comfort of summer, our thoughts may shift to a new rhythm emerging in our agricultural landscapes.
Thirty years ago, when I first shared responsibility with farmers on when to plant, the seasons had a predictable cadence. Don’t plant too early, lest you risk the early frost. These days, it seems the soil is ready earlier each year for seeds to be sown while the calendar still declares spring.
The topic of climate change shouldn’t be confined to discussions of melting polar ice caps or rising sea levels, it should be discussed here at home, and how it may affect our fields and our livelihoods. It's described as a series of complex shifts in our planet's weather patterns, temperatures, and ecosystems, attributed to an increase in atmospheric greenhouse gases. Whether this is a reality, a prediction, or a model yet to be proven, one thing is clear: it's a conversation that's shaping our understanding of farming in the Prairie State.
Over a good portion of my career, I oversaw the management of farms in the Mississippi Delta. Farming in the Delta has an entirely unique set of challenges we don’t typically see in the Midwest. While no one is predicting that farming in the Midwest will become more like farming in the Delta, perhaps there are some things we can learn about farming in a warmer, more weather volatile environment. Which, if predictions hold out, could potentially become a more frequent scenario in the Midwest.
Droughty Conditions
The Delta region generally receives more rainfall than the Midwest, with annual averages close to 80 inches in the wettest parts of the country. In contrast, the average yearly precipitation for Illinois varies across the state, with the southern tip receiving about 48 inches and the northern portion receiving about 35 inches.
One would wonder that if the south receives so much rainfall, then why do so many farms in the Delta rely on irrigation to grow crops?
Well, it's not just the quantity of rain that matters for agriculture, but also its timing. Farms in Illinois receive much of their rain during the spring and summer due to warm moist air from the Gulf colliding with cool dry air from Canada over the Midwest during those seasons. The Delta receives much of their rainfall during the fall and winter months when seasonally cooler weather pushes those systems southward.
One potential impact of climate change is the poleward shift of weather systems, including cold fronts. The Arctic is warming faster than the tropics, which reduces the temperature contrast between these areas and can cause the jet stream (a band of strong winds in the upper levels of the atmosphere that often guide weather systems) to shift poleward.
If that happens, then there is potential for the timing of rainfall in the Midwest to shift from Spring and Summer to Fall and Winter. I have not read anywhere where this is predicted, but from my layman’s logic, it is something I wonder might happen in the future if our climate is changing.
What does that mean for farming in the Midwest?
Well, fortunately the soils are much better up here than down there. The water holding capacity of prime Illinois Prairie ground is among the best in the world. In contrast, the soils of the Delta are made up of mostly clay, washed down from the soils of the Midwest. When drought comes clay holds on to water tightly giving up sparing amounts for plants to grow. Not so with the Prairie soils. We can weather droughty conditions better because of it.
Farming practices that encourage the soil to hold its water such as utilizing cover crops may become more important over time.
In the long run, or perhaps very long run, I could see farms that have access to water for irrigation hold on to value better than land that does not if droughty conditions prevail.
Intense Rainfall Events
Another characteristic of farming in the Delta is dealing with intense rainfall events. I remember growing up a 3- or 4-inch rainfall was quite the downpour. Now, we can see events that produce up to 10 to 12 inches of rain at a time. This is something farmers in the Delta have had to deal with for a long time.
With the effects of climate change, increasing temperatures tend to lead to increased evaporation, which in turn leads to more precipitation. This has been observed over the past century, with an increase in the number of heavy precipitation events over many areas. Eastern portions of North America, including the Midwest, have become wetter, with the total annual precipitation increasing at an average rate of 6.1 percent per century since 1900. Specifically, the East North Central climate region, which includes parts of the Midwest, has seen a significant increase in precipitation (11.6 percent per century).
Drainage is almost as important to farming in the Delta as is irrigation. You got to get the water on, but you also must be able to get it off.
In the Delta, much of the focus is on surface drainage. The low water permeability of their soils means that subsurface drainage is not usually cost-effective. Not so in the Midwest. Compared to the Delta, our soils sponge up water. We’ve already seen a push for more tile to be installed. I don’t see that decreasing if Climate change is a factor.
Conservation practices will become more important. As anyone who has been through a toad-choker can attest, not all of that water is soaked up by the soil. There is a lot of runoff and that runoff carries our soil with it.
The old conservation standard T by 2000 sought to limit soil loss to between 1 to 5 tons per acre per year depending on the soil type. That is what is considered sustainable, replenished by naturally occurring processes. Beyond that, we lose soil forever.
What does permanent soil loss look like?
Let’s say that a farm loses 3 Tons per acre beyond what is sustainable. Three tons of dirt spread over an acre is about the thickness of a dime. A dump truck will hold 15 tons, or about 5 acres of that soil. If your farm is 160 acres and it is losing soil the thickness of a dime every year, then that’s the equivalent of 32 dump trucks showing up to your farm to cart the dirt away. Every year.
Employing conservation practices such as filter strips, CRP, and cover crops to save your soil may become more important than they are now.
More Pests
Another characteristic of farming in the Delta is dealing with more pests than what we see here in the Midwest. Longer grower seasons and fewer or lack of freeze events contribute to farmers dealing with more insects, weeds, and disease in the Delta.
Rising CO2 levels, a key factor in climate change, can stimulate weed growth and make them more resistant to herbicides. Weeds often grow faster and are more adaptable than cultivated crops. With an increase in temperature, the geographical range of many weed species could expand, leading to increased competition for resources with crops. This could affect yield and force changes in farming practices, including increased use of herbicides, which can have further environmental impacts and increase cost of production.
Warmer temperatures can also lead to expanded ranges and increased population growth rates of many insect species. Resulting in increased pest pressure on crops. Warmer winters may also allow more insects to survive over the winter, leading to larger populations in subsequent growing seasons. These changes can lead to greater crop damage and increased use of pesticides.
Climate change can influence the prevalence and severity of plant diseases in several ways. Warmer temperatures and changes in rainfall patterns can create conditions that are more conducive to the spread of certain diseases. Warmer temperatures can also allow disease-causing organisms to expand their geographical ranges. Furthermore, stress from climate change can make plants more susceptible to diseases.
In the Delta, the payoff for adaptive thoughtful farm management practices is huge. Competent management through increasingly harsh environments may become increasingly important for farmland owners in the Midwest.
As we anticipate the evolving future of farming in the Midwest, potential shifts in climate patterns warrant our attention. Possible changes in rainfall timing, the prospect of more intense precipitation events, and the potential rise in pest populations present new factors for consideration in our agricultural practices. Yet, these potential shifts also provide opportunities for learning and adaptation. From the robust soils of the Prairie State to the weather-resilient strategies of the Mississippi Delta, we have a wealth of resources to draw upon. The future of our farming success will depend on our adaptability, innovation, and commitment to sustainable practices. Although the exact future of our climate remains uncertain, our determination as stewards is unwavering. As custodians of this land, we must continue to monitor, learn, and adapt to whatever changes may come, ensuring that your farmland continues to thrive for future generations.
