From drought to flood conditions, it seems there is no longer a “normal” growing season for Indiana farmers. A year of extreme heat and drought in 2012 was followed by a cool, wet spring. These types of weather extremes can be very damaging to Indiana’s soils, but farmers who are applying soil health practices like cover crops and no-till are benefitting the most.
Besides cover crops and no-till, conservation practices that improve soil health include crop rotations, and responsible nutrient and pest management applications.
April 2013 set records in terms of rainfall for parts of Indiana, with several central Indiana counties receiving four to six inches on April 19. Traditional erosion control practices – like buffer strips, filter strips, and grassed waterways –held up well during these rains. The rains have continued to fall, but Barry Fisher, State Soil Health Specialist, with USDA’s Natural Resources Conservation Service (NRCS) in Indianapolis, says soil health practices provided additional protection from erosion caused by heavy rains.
“In fields where the soil was disturbed through tillage, there are some rough areas with a lot of soil erosion,” said Fisher. He further explains, in fields with high amounts of crop residue left from no tillage, “there was significantly less erosion, and in fields with no-till plus cover crops, there was little to no erosion.”
Thousands of Indiana farmers have attended the over sixty annual workshops put on by the Indiana Conservation Partnership (ICP) and the Conservation Cropping Systems Initiative (CCSI). These workshops focus on ways to integrate cover crops, no-till, nutrient management and precision farming into successful cropping systems that improve soil health and resilience to extreme weather. As a result, the ICP estimates that farmers planted over 500,000 acres of cover crops in last fall.
“This is a difficult number to estimate,” said Fisher, “but in my conversations with numerous seed industries, agricultural retailers, agencies and groups who are tracking these acres, I feel this estimate maybe conservative.”
Fisher says that cover crops with no-till will undoubtedly help reduce the impact of heavy spring rains. “We are promoting cover crops to increase soil organic matter and water infiltration rates, and to limit nitrogen leaching,” he said, “but erosion reduction is an additional benefit during heavy fall and springtime rains.”
One farmer who reaped the erosion control benefits of cover crops is Larry Timm who farms in Putnam County where some of the heaviest rains have fallen. His cover crop acres protected the soil very well after receiving more than five inches of rain in 24 hours. In areas where he has no-till fields, but no cover crops – erosion was visible.
“Where rye grass was part of the cover crop system this spring even with the heavy rains there is no erosion showing up,” said Timm, adding, “The rye grass even continued to pull excess soil moisture in the early spring, which allowed me to plant earlier than on fields without cover crops.”
Timm expects to see even further benefits from cover crops as the year goes on, especially if the weather turns hot and dry.
According to NRCS District Conservationist Matt Jarvis, farmers planted more than 2,315 acres of cover crops in Putnam County last fall. Most of the acres were planted as part of one of NRCS’s programs, however Jarvis explains that many farmers see the benefit and plant cover corps on their own.
“Ironically, many of our farmers used 2012 drought assistance funding to plant cover crops to help feed the soil and to take up excess nitrogen. This spring those cover crops are also protecting the soil from erosion,” said Jarvis.
Shannon Zezula, state resource conservationist for NRCS in Indiana, says the “cover” that cover crops provide is only part of the erosion control benefit. Zezula points out, “Any ground cover protects soil from taking a beating from the force of falling raindrops. Crop residue and living plants protect soil aggregates from crumbling under the hammering energy of raindrops.”
Zezula recommends cover crops because they provide food for microorganisms, which in turn provide “sticky” substances that stabilize soil aggregates. “This also improves water infiltration and aeration,” he says.
Indiana’s growing numbers of soil health farmers are well into planting since the rains have let up, but as you can guess, they are already planning for fall cover crop plantings.
For more information about practices to help improve soil health, visit your local NRCS office or go online to www.in.nrcs.usda.gov.
(Photo by Barry Fisher, USDA NRCS: Vertical tillage, plus pre-plant Anhydrous Ammonia injection made for just enough soil disturbance to give spring storms the opportunity for sizable loos of soil and expensive nutrients)