After a severe winter and late wet spring, summer came very late this year in the American Midwest, leaving most farmers more than a month behind in their planting schedules.
This is a concern in North Dakota and Montana as there are only roughly 120 frost-free days in the year, with temperatures ranging between -30C and +40C.
In Minnesota, two weekends early last month saw eight inches of rainfall cause extensive flooding, and while heading towards Montana we went through a ‘twister’ and saw five trucks blow over on their side in the space of 10 minutes.
Average rainfall varied from 29 inches in Minnesota to 14 inches in the eastern part of Montana.
I was there in mid-June on a one-week, 1,800-mile tour led by French no-till and cover crop enthusiast Frederic Thomas. Most of the 40-strong party were French farmers.
At the University of Minnesota we were shown permanent cover crops such as Kura clover (Caucasian clover) into which corn was direct drilled.
The clover is a winter-hardy nitrogen-fixing legume with deep taproots and rhizomes. It also has the advantage of being glyphosate tolerant.
Minnesota originally had a large number of livestock and dairy farms, and agriculture has now shifted to being mainly crop-based, relying heavily on corn/ soybean rotations.
The university was therefore actively looking at developing other crops that could be profitable and grown in the area, such as pennycress (oilseed with a very high oil content) and wheatgrass, a perennial which is very persistent.
Wheat is grown on farms to the west of the Dakotas and into Montana, even though the economics don’t appear to stack up compared to growing corn and soybeans. The advantage lies in the opportunity to establish cover crops in time before the winter, which was virtually impossible after harvesting corn and soya.
Crop rotations varied across the Midwest from purely corn-soybeans rotations to variations of corn, soybeans, peas, wheat (winter and spring), oats, barley, canola, sorghum, sunflower, flax, barley, lentils and some speciality crops.
Cover crop mixtures were diverse, and were either sown in the autumn as cool season covers mainly after wheat, but also in the spring and summer as warm season covers.
Together with practising no-tilling, farmers were seeing benefits to their soil structure and organic matter content.
Biological activity in the soils was improved, as was drainage in the wet periods and moisture retention in the dry periods.
Soil temperatures are more stable and there is a vast array of cover crop species grown including tillage radish, phacelia, lucerne, rye, peas, oats, rapeseed, millet, sunflower, sweet clover and vetches.
Dwayne Beck, manager of Dakota Lakes Research Farm near Pierre, South Dakota, has been no-tilling on his own farm for 30 years.
“On average, most sloping land in the Midwest has only about half the organic matter and half the topsoil that it had when it was first cultivated,” he said.
In the past prairies flourished with a diversity of plants, a minimum amount of disturbance, and living roots that grew throughout most of the year.
Farmers, however, reaped the benefits in the early years after the virgin soils were first cultivated. Using a diverse range of cover crops as well as no-till, Dwayne is trying to emulate the ecosystem functions of natural prairies.
He also states there is no need to fall back on occasional tillage as “one year of tillage destroys the environment for microorganisms you’ve been building for years.”
Jay Fuhrer of the United States Department of Agriculture, based at the Menoken Farm research site at Bismarck, North Dakota, has been studying and recommending soil health measures for 20 years.
He believes most farmers don’t have enough crop types in their rotation in the Midwest, and that using 10-12 species in a cover crop rather than one or two can accelerate biological time, leading to a more balanced biology below ground.
His main keys to improve soil health are minimising soil disturbance and providing protective armour (cover). There should always be live roots growing in the soil and diverse plants and rotations. Where possible, animals should be used.
Recent research has shown the less you till, the more carbon you keep in the soil to build organic matter. Mineralisation in no-till soils is also more evenly spread over the season rather than the ‘boom or bust’ pattern under tillage-based systems.
To help farmers realise and address these points a Natural Resources Conservation Service was established in the 1930s as a result of the ‘dustbowl’ issues of that era.
It works with farmers to regenerate degraded soils and, with people in the organisation like Jay Fuhrer and Ann Fisher, they are getting the message across: advocating minimising soil disturbance, providing soil cover, switching from a monoculture crop to a diversity of crops and rotations, and always having roots growing in the soil.
Not only is soil health looked at, but the changes being advocated must also take account of ‘quality of life’ and we did see some farms where this had improved considerably as a result of changed farming practices.
Hiring skilled labour was an issue for many farmers due to the booming oil business in North Dakota and Montana.
On our on way back east we visited Gabe Brown and his son Paul who farm 5,000 acres, of which 3,000 are tame or native pasture, outside Bismarck, North Dakota.
He started farming in 1991 conventionally and suffered a series of weather-related setbacks.
Between 1995 and 1998 he lost more than 80% of his crops due to hail and drought.
With these disasters he realised he had to try to
farm without synthetic inputs.
Today he achieves 25% higher yields in his cash crops without synthetic inputs, except for some pre-planting herbicide every two to three years, through using 100% no-till and a permanent cover on his land, with a high diversity in species grown of all crops.
His average organic matter content has risen from less than 2% in 1993 to more than 6%.
They also carry 350 Aberdeen-Angus cow and calf pairs, direct retailing much of the finished progeny at around 550kg for three to four times the market price.
He aims to breed small and easily fleshed beasts off poor quality forage.
Most of the ranchers we met still sold their calves as yearlings to feedlots, but there was a growing trend towards finishing the cattle themselves.
When we visited the Browns we saw 220 Aberdeen-Angus cow/calf pairs and four bulls mob grazing a 75-acre field of flowering triticale which they were on for 18 days, being moved daily with the bulls only running with the cows for a month.
The cattle noticeably did not think the forage to their liking, but they use their cattle as a tool to improve the soil health.
A 15-20 species ‘warm season’ cover crop is then direct drilled into a heavy mat of the triticale residue as soon as possible after the cows are out.
Like many of the other farms we visited that had livestock, calving has been delayed from a traditional February/March time to May/June, which is more in tune with nature and the growth of the fodder in the spring.
Most farmers outwintered their cattle on mature grass, harvest residues (corn stalks) and cover crops.
It was originally thought only bison could get at the grass under two to three feet of snow, but the Aberdeen-Angus cows are quite adept at it as long as there is no ice.
Buffer feeding is commonplace in exceptional weather conditions, and calves are weaned at 11 months in late March.
It was a thoroughly informative trip, everyone was open, friendly and hospitable in true American style.
It was very different to farming in Fife, and I have come back to the country with a few ideas to try out.
* Douglas Christie farms at Durie near Leven.