Gamma Rays Detect Nutrient Levels – Agronomist & Arable Farmer – Oliver Wood

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TerraMap soil scanning infographicUsing technology to map soil nutrients is not a new science; however, a newly launched system takes the process to a whole new level.

Launched by Hutchinsons, TerraMap revolutionises the way in which soil nutrient mapping is undertaken. Today's precision farming requirements demand greater accuracy and UK growers do not currently have access to a high definition soil scanning system – until now, says precision technology manager Oliver Wood.

TerraMap uses gamma ray detection technology that delivers resolutions of over 800 points/ha, providing high definition mapping of all common nutrient properties, pH, soil texture, organic matter (OM) and the Cation exchange capacity (CEC) of the soil, as well as elevation and plant available water.

"With such a growing level of interest in soils, the launch of TerraMap comes at the perfect timing for farmers that are looking for that next level of accuracy in understanding their soils," Mr Wood says.

"We have been looking for a new method of mapping soils that provides more accurate and repeatable results, and can also leverage the multi-layer analysis within Omnia."

The results from TerraMap are used to create maps within the Hutchinsons Omnia system, which can then be overlaid with additional field information such as black-grass and yields to create the most accurate, consistent and detailed variable rate plans.

Terra Map - Soil OptixData collection scans are carried out by driving a lightweight all-terrain vehicle fitted with the sensor over a field, and then taking soil samples to allow for each scan to be used to create the individual map layers.

Manufactured by Canadian company SoilOptix, TerraMap's scanning technology is based on a scaled-down version of airborne sensors first used in mineral prospecting.

It measures naturally emitted isotopes like caesium and potassium that are very stable due to their long half-lives. "The significance of this methodology is that it is not affected by soil moisture, compaction, crop cover or cultivation state," Mr Wood adds.

"This means that there are very few limitations to when TerraMap can be used – offering a much wider operating window compared to other soil scanning systems.

“We have taken satellite imagery of fields that showed up areas of soil differences quite clearly and when we overlaid this with the texture maps created by TerraMap, they were identical. This has been confirmed by in-field ground truthing across a number of sites.

"We have also tested the results between seasons and over different cultivations and they have remained consistent.”

It was on this basis that Andrew Crossley, manager at Suffolk-based Thurlow Estates, trialled TerraMap.

"We had used another scanning service back in 2012 and it threw up some questionable results, which we put down to interference to the scanning from the chalky soils and changes in soil structure but nothing was conclusive," he says.

"When we were introduced to the TerraMap system, we felt that it would work well with our soil types so it was worth giving a go. The results have been impressive and are more accurate than
previous results.

"We look forward to seeing how this will integrate this autumn with our precision farming to give us more accurate variable rate plans, especially on our chalky soils."

TerraMap is available from Hutchinsons in a standard (£24) or premium service (£32) offer.

The standard service measures 9 criteria: P, K, Mg, pH and % of clay, sand, silt, texture and elevation. In addition to these, the premium service also measures calcium, sodium, manganese, boron, copper, molybdenum, iron, zinc, sulphur, OM, CEC and plant available water, delivering 21 layers of data for each field.

TerraMap Layers