Soil Health, Risk Management, and Wildlife: Observed Benefits of Cover Crops and No Till
Spring has finally sprung in central Wisconsin. After a Mother’s Day dusting of snow temps have finally climbed to the seasonal average, but precipitation continues to inundate fields with moisture. Planting is delayed across the region for corn and bean acres. Further complicating the spring weather is widespread winter kill of some alfalfa and winter wheat fields. In light of all of this I have noticed some important changes to my no till cover cropped acres; from soil biology to weed populations to field accessibility.
But first, a busted myth on soil temperatures
The soil temperature of a no till cover crop field shows 63 degrees.
Out of curiosity, I took a couple of soil temperature measurements; one in my no-till cover cropped field that currently has winter wheat, and one from my neighbor’s conventionally tilled field across the fence row. All other things the same (precipitation, drainage/slope, soil type) there was a considerable and surprising difference in soil moisture, quality and temperature. My soil was moist, but didn’t have excess moisture and had good tilth; like chocolate cake. My neighbor’s field could best be described as holding excess moisture and poor tilth, falling apart into a thousand pieces. But the biggest surprise was the difference in soil temperature.
Most farmers hold the belief that no till cover crop fields are wetter and colder than conventionally tilled fields. Soil temperature readings showed my neighbor’s heavily tilled soil at 54 degrees and my no till cover cropped field at 63 degrees. (Thanks to Dave Robison for first examining the soil temperature question: http://plantcovercrops.com/myths-debunked-on-cover-crops-and-colder-soil-temperatures-final-report/). Improved drainage has made all the difference. And for me, no till and cover crops provide the best drainage system.
Cover crops and No till help me to mitigate the impact of poor field conditions caused by continuous rains
Despite heavy rains that have prevented most field work on tilled fields in the area, I have been able to move forward with my management thanks to no till and cover crops.
What’s more, the improved soil tilth and drainage have improved the accessibility of my land. With rain every other day for the past three weeks, few farmers in this area have been able to accomplish much field work. Under conventional till, soil tilth and health are compromised, requiring more time for soil to dry out and requiring drier conditions to allow field work. When other farmers could not even get a tractor into their fields, I was able to have the co-op fertilizer truck broadcast fertilizer without leaving so much as an indentation or track. Improved soil health through no till and cover crops has reduced weather related delays to implementing good farming practices. Had I decided to use my winter wheat as a cover crop, I could have easily terminated it and had time to plant corn or soybeans. In the meantime, conventional farmers are still waiting on the weather to begin spring tillage and will likely experience reduced yields due to delayed planting.
Microorganisms and wildlife returning to no till, cover cropped acres
Most of this winter wheat field has little to no weed pressure yet.
Finally, while walking through that same winter wheat field, now in the third year of transition to no till, I noticed two other significant developments: considerably reduced weed pressure and significant growth in biological activity. With surface residue from previous crops, weed seeds are having less success germinating. Additionally, the biological activity continues to increase. Signs of life abound; from surface insects to tremendous worm populations. In a single garden trowel scoop of soil I have found upwards of 10 or 12 worms. All of this activity not only benefits my soil health, but wildlife and the natural world as well.