A new agronomy system developed in Scotland aims to put integrated pest management into practice, thereby helping growers spend less on crop inputs while maintaining yields.

Its principles can be applied to any crop or farm and it begins by confirming soil status on a field-by-field basis.

See also: How a winning mixed soil farmer cut arable crop inputs

Hybrid Farming Systems, established by Scottish independent agronomist Andy Cheetham, combines organic and conventional farming practices to help reduce reliance on artificial chemicals.

Assessing crop nutrition, soil cation exchange capacity, and use of natural crop inputs is the system’s core focus. 

“The hybrid system is unique in the fact it uses historical information to optimise yields, backed by a full soil survey with Adas and SAC data to determine soil-limiting factors,” says Mr Cheetham.

A full survey of the physical, chemical and biological status of the soil is carried out using a unique soil-balance analysis system.

It also provides detailed analysis on mineralisable nitrogen, organic matter and carbon levels. Funding is available in Scotland for carbon audits, which allow access to funding for soil analysis.

Targeting soil-available nutrients

Unlike many soil samples, this system assesses both soil- and plant-available nutrients, where up to three tissue analysis tests are taken throughout the growing season to tailor nutrition programmes.

For example, Mr Cheetham notes that phosphate-mapping capacity carried out across Caithness and Aberdeenshire revealed up to 75-100% of soil-applied phosphate is locked up and unavailable to crops and livestock, due to naturally high aluminium oxide and iron oxide levels in soils.

“A conventional soil test would provide a phosphorus (P) index of 5 or 6, but in reality, very little of this is available to the plant. Only when a tissue sample revealed “low” levels would growers realise there was a problem,” he says.

However, the solution is simple. “Simply reduce the amount of granular applied phosphate and switch to a phosphite seed treatments and a foliar spray to feed the leaf direct.”

Crop nutrition

The next stage is choosing the correct nutrition source for the job.

“Crops require nitrogen for establishment, but not in excess. About 30-50kg N/ha is adequate for successful cereal establishment, depending on soil reserves.

There is often at least 50kg N/ha available to crops in a naturally mineralised form in the soil reserve, which can be forgotten about,” he says.

A strong focus is placed on broad spectrum tissue analysis in order to confirm levels of essential nutrients, particularly nitrogen at three key timings:

• Two to three leaf stage
• Tillering
• Flag leaf stage

A strong focus is also placed on potassium, a very important nutrient with regards to stem strength, and both drought and frost protection in crops.

“About 90% of my farmer clients growing spring barley traditionally used the maximum Nitrate Vulnerable Zone limit of 130kg N/ha in granular form. They have now cut this rate by more than 50% to just 60kg N/ha without impacting yield and quality, with average yields of 6t/ha and a bumper harvest of 9.8t/ha.”

He notes the remaining 10% applied no nitrogen fertiliser at all, again with no impact on yield or quality.

Mr Cheetham now recommends liquid fertiliser sprays for their reduced losses and accurate applications right to the field boundaries.

He avoids dribble bars as they scorch leaves, and instead uses Lechler UAN nozzles to reduce this and improve foliar coverage. He also suggests amino acid liquid sprays to provide a direct protein source to crops.

Weeds and disease

Where possible, Mr Cheetham advises weed control be carried out using contact acting herbicides, which reduce crop stress. “Some sulfonylurea products are very hard on the crop and cause stress and increase disease risk.”

Ramularia is the biggest disease threat in spring barley, particularly after the loss of chlorothalonil. He finds an effective control in spring barley is Lentyma (fluxapyroxad + mefentrifluconazole) plus Bittersaltz (magnesium sulphate) + Scyon.

Scyon is a complex of metabolites designed to maximise plant health and has an important role in fungicide support and anti-resistance.

Containing natural sugar-based properties, it helps maximise crop health by “biologically priming” the plant for a faster and stronger defence response.

The variety Golden Promise is a popular choice in Northern Scotland due to being two to three weeks earlier ripening than other varieties.

Mildew can be an issue, but is effectively controlled using a sulphur spray before the disease has time to take hold.

Where the disease has established, he recommends a foliar feed based on seaweed, manganese, copper and zinc. This has been trialled alongside mancozeb with very promising results.

For organic spring barley, Laureate is a strong choice with its good disease profile, where restricted use foilar feeds can be applied for rhynchosporium and ramularia control.

“A question I get asked all the time is “can I increase yield when all plant numbers are determined?. The answer is yes, as there are a number options to increase specific grain weight – the heavier the grain, the bigger the yield.”

He advises farmers to do what they do when crossing a road – stop, look and listen.

“Don’t just take your advisors or agronomists word for it, ask why they are using specific inputs? The Hybrid Farming System is not a one recommendation fits all.

“Every field is different and this system works at the field level. Be brave and try a couple of fields using this system. You may be surprised at how much you can save without affecting yield or quality.”

To get in touch with Mr Cheetham email: ceresagriservices@gmail.com