IN agriculture's genetically modified (GM) cropping revolution heartland it's not easy finding a large-scale United States graingrower who chooses to plant soybeans which are non-GM.
But in the US Midwest the Miller family's sizeable 8000-hectare cropping enterprise in North Dakota has defied the odds to achieve handy gross margin benefits by staying well clear of GM beans.
The US Department of Agriculture estimates about 90 per cent of the US corn (maize) crop and even more of this year's soybean area were planted to GM varieties.
Yet while impressive yield gains and simplified herbicide management regimes have fuelled GM's popularity explosion in the past 15 years, the Millers are notching up better returns from non-GM markets.
Increasing problems with weed resistance to herbicides are also making their neighbours think twice about their cropping programs.
Weed costs are rising as farmers are forced to resort to a mix of spraying strategies to clean up glyphosate resistant plants.
"We're seeing more and more weed resistance around here," said Casey Miller, who with his brother Jon has run the sizeable family cropping and grain storage business since taking over the from the father in the 1980s.
"Soybean prices are now much lower than they've been for while, so it's getting harder to absorb extra growing costs.
"GMs all started out good and easy, but feelings are starting to change now.
"This area grows a lot of sugar beets. There's increasing resistance to Roundup showing up in the beets."
About half the dryland cropping area on the Mill Farms aggregation in the Red River Valley is planted to a non-GM soybean varieties sold for a premium price.
Some of that premium is compensation for the extra work associated with guaranteeing the crop's GM-free status.
The price bonus also makes up for certain non-GM varieties which yield less than than GM crops.
However, some strong performing varieties grown by the Millers were bred specifically by the family in partnership with private plant researchers.
The crop is stored on farm in an 81,600-tonne capacity silo complex, sited alongside a railway line with associated grain drying and grading facilities.
Mill Farms also plants 2000 hectares to both spring wheat and corn in a continuous cropping program rotating with soybeans.
An annual average rainfall of about 560 millimetres (22 inches) typically delivers yields of about 8.7 tonnes per hectare (140 bushels per acre) for corn; 2.3t/ha (34bu/acre) for soybeans; and 3.4t/ha (50bu/acre) of wheat averaging about 14pc protein.
To get everything harvested before freezing, snowy weather starts setting in by late October, the business has six headers, all fitted with tracks to handle the boggy conditions which invariably plague the end of the cropping season.
Generally the oldest two harvesters are replaced each year.
"We probably only need three combines for the amount of crop we grow, but the weather conditions make it slow work," Jon Miller said. "We're always fighting moisture."
The farming business also has six high horsepower Case IH Steiger Quadtrac tractors and two Steiger Rowtrac units.
Fertiliser is delivered by rail and stored and blended on the farm.
Not far from the family's big grain storage silo stands a flour mill, also built by the Millers.
Although sold to another operator a decade ago, it continues to provide a nearby market option for their wheat at minimal freight cost.
Mill Farms employs up to 15 staff and is now also jointly managed by the Jon and Casey Miller's respective sons, Travis and Dallas, who are the fourth generation on the family holdings, located near the North Dakota-Minnesota border city of Wahpeton.
Their grandfather, Ivan, began accumulating much of the aggregation in the 1960s when land was "fairly cheap and easy to buy" from farmers looking to retire.
These days farmland in the district sells for $11,100/ha to $13,700/ha ($US4000 to $US5000/acre).
Much of the Miller aggregation was originally rented, to be later acquired by the family, but holdings are spread over a 55-kilometre distance and consist of about 150 blocks.
"About a quarter of our hours at harvest are spent moving gear around," said Casey Miller.
Andrew Marshall visited the US as a guest of Case IH.