Farmers are the greatest manageable variable affecting wheat yields, says British consultants who run yield networks of top producers.
The biggest difference is not region or variety, or soil type, says Roger Sylvester-Bradley, with ADAS, the largest agriculture consultant group in the United Kingdom.
Instead, the largest effect on yield is firstly a mix of “interactions with the season,” which Sylvester-Bradley calls a “fog” of the many factors, including weather, that influence a crop in a given year. The second largest yield impact is the farm and especially the farmer.
That makes sense because while collecting extensive data on farm practices from farmers who are part of Yield Enhancement Networks (YENs), the researchers have found that there’s little regional effect. There are farmers getting high yields in many areas of the U.K., with many different soil types.
Sylvester-Bradley, who spoke at the Southwest Ag Conference recently in Ridgetown, along with his colleague Ruth Wade, looks at farm level and field level data, some he came to late in his career after he realized the small plot work he’d been doing for years and the wheat nutrition recommendations he’d been making for as many years, were wrong.
His work has convinced him that there’s great room yet for increase in crop yields. If the major factors are those managed by humans, then there’s potential for other humans to also make the same choices.
“If you have huge variation in yield, it proves improvement in yield is possible,” he said.
From 2002 to 2018, 477 variety trials, and 14,000 plot yields have been recorded by ADAS. Wheat yields have ranged from 50 to 275 bushels per acre.
He calls for more “farm-centric learning” that allows a farmer to boost their yields taking into account the factors on their farm. Scientifically proven recommendations aren’t enough. They have to be married to practice.
He says the difference among farmers isn’t that they’re investing a lot more than others in crop nutrition, or protection, but they have applied more attention to detail. They get the crop nutrition level and applied at the right time, repeatedly.
Sylvester-Bradley and his colleagues are also working to redefine what constitutes “yield” in the minds of farmers.
A volume measurement, like bushels per acre or tonnes per hectare is too simplistic. He’s looking for “edible yield”, something that includes quality factors and the ability of the crop to convert sunlight to final product.
One of the many numbers that the YENs capture includes solar energy measured in terrajoules.
They also look at how much water is captured by plants in a field.
“I wonder how many of you know how much water your soils hold? If we know that, we can get to 300 bushels (per acre of wheat),” he said.
As a result of all of that research, farmers in the Yield Enhancement Networks can compete on actual yield out of their fields and on potential yield – if they had better luck with sun and rain in a particular growing season, says Wade.
Each farmer in the YEN, which now numbers about 250, gets a 20 page report on their farm’s productivity benchmarked against aggregated numbers.
Actual yields reached a high of 248 bushels per acre in 2019 for the winner.
Sylvester-Bradley says the huge yield that the winner got this year is in soils that the textbooks say couldn’t hold enough water to get that yield.
“Clearly the textbooks we’ve been relying on for years are wrong,” he said.
The Yield Enhancement Networks have spread into other crops, including a new one in Prince Edward Island for potatoes. There’s a new one in the U.K. that focuses on crop nutrition, because Sylvester-Bradley says there’s lots yet to learn in that area.
Tomatoes grown hydroponically can produce huge biomass – including 28 tonnes per hectare of saleable product and 430 tonnes of wet biomass.
That yield comes from increasing carbon dioxide in the greenhouse and precisely feeding water and simple salts the provide the plant with 12 essential elements, he says.
In the field, a healthy soil must also be capable of supplying those 12 essential nutrients, in the varied amounts necessary, from hundreds of pounds of nitrogen and potash to single grams of molybdenum per hectare.
ADAS is looking to identify whether nutrients have made it to the grain at harvest and use such measures to identify nutrient deficiencies. They are doing that by measuring grain, but also doing leaf analysis while the crop is growing, although Sylvester-Bradley says better standards are needed for interpreting leaf analysis.
High wheat yield findings from the U.K.
- 15 tonnes per hectare is possible almost anywhere in the U.K.
- It’s less about what you spend, more about attention to detail
- Large yields come from large crops (able to capture sunlight and water)
- Taller crops with higher straw nitrogen percentage tended to have higher yield
- Good nutrition, control of disease and reducing lodging risks
Farm management factors affecting high yield:
- Growing wheat after a break crop
- Narrow drill widths
- Using manure
- Applying adequate nitrogen
- Several applications of plant growth regulators