Why we use precision decisions for our soil sampling

“Precision decisions clearly explain and help me to understand what they sell, especially where soil services are concerned, and that makes me confident in what I am doing” ‐ Tamara Hall, Molescroft farm.

Peter Marston farm manager, Stittenham farms and Tamara Hall, Molescroft farm on the soil services that precision decisions supply.

Peter Marston the farm manager for 39 years at Stittenham Farms to the north of York started soil testing in 1998 with Clive Blacker, prior to Clive setting up Precision Decisions (PD) in 2004. He farms 1600 acres and has this land sampled on a 4 year cycle.

Tamara Hall at Molescroft Farm near Beverley runs a 1500 acre operation and first came across Precision Decisions about 10 years ago when she first looked into variable rate (VR) farming. She has been working with PD for both soil sampling and scanning since she became an early convert to VR farming techniques through using the Passive YARA N‐Sensor as an accurate means of variably applying her liquid nitrogen. Similarly Peter has also operated a Passive N‐Sensor for many years and sees the value of VR farming techniques, especially when dealing with highly variable land and soil
which both these farms have to contend with. Both farms use the soil nutrient results that we supply them with to produce variable rate P & K application maps.

Peter and Tamara both value the straight forward advice that Clive Blacker and the team at Precision Decisions give.

As Peter said, he has always remained a loyal customer of Precision Decisions because;

“I like to work with Clive and the team at PD, they have always been at the forefront of variable rate technology and practices and I see their soil services as an important part of my approach to my land and crop management issues” 

Tamara similarly said;

“Precision Decisions clearly explain and help me to understand what they sell, especially where soil services are concerned, and that makes me confident in what I am doing”. She went on to say, “PD give us sound advice, you explain things simply keeping the baffling science to a minimum”


Both Peter and Tamara approach soil sampling and the subsequent VR application maps in the same way. They use GateKeeper (GK) to send PD the plan for the year’s soil sampling tests, once the sampling results have been returned and imported back into GK. They then, often with the help of overlaid maps such as N‐Sensor biomass maps and yield maps, produce VR application maps for P & K. Both farms put down most of their Nitrogen variably by spraying it utilising the ‘live’ N‐Sensor technology. Peter has found that over the years he has ironed out much of the inherent variability in his land producing a much more even crop and yield, whilst reducing the risks of crops laying down, he augments this through the use of the N‐Sensor.


Stittenham farm soil sampling p & k indexes 2017 and 2014

Sampling results for 2017 P after VR application of P as a result of Sampling results for 2014 P index.
Although some balancing remains to be done in the NE corner of the field the remainder of the field is much more even.

Sampling results for 2017 K after VR application of K as a result of Sampling results for 2014 K index.
This field had successfully had its low Potassium issues successfully rectified as a result of soil sampling by PD.

Both farms differ in their approach to VR drilling. Initially Peter did try VR drilling. With the help of Clive Blacker he adapted the software on an old RDS fertiliser controller to control a Simba drill variably through an actuator. On poor areas of land producing poor yields he drilled his seed up to 50% more densely through VR maps. Eventually Peter moved away from deep ploughing to a Min‐till approach which produced much better seed beds on his strong land and thereafter he did not
continue with VR seed.

Tamara Hall of Molescroft Farm, Beverley East Yorkshire
Tamara on the other hand has developed her approach to VR drilling. Soil results both sampling and conductivity scans are key to her approach. PD tests on a 3 year cycle for pH, P & K levels. Initially the soil results did not correlate with yield maps. Tamara felt that this was because of inherently high moisture levels due to the high water table on which her land sits supplying high nutrient levels. The soil results have allowed her to replace the nutrient offtakes of P&K through VR applications and now after 3 cycles over 9 years she is happy with levels of generally 2 for P and greater than 2 for K. She has recently strengthened the value of these soil sampling results with soil conductivity scans taken during 2009/10 and 2016/17 to give an accurate cross comparison of soils, interestingly the heaviest land from the scans showed as the worst black grass areas on the farm.

Molescroft Farm Soil Conductivity Scan

This is a Shallow Conductivity (50cm) of one of the fields at Molescroft Farm.
Represents the variance in the top 50cm of the soil only, giving a good indication of the soil conditions which could significantly influence drilling conditions and emergence of the crop. In this map the higher the number the heavier the soil. The lower the number the lighter the soil.

Tamara now produces her own VR seed plans and applies these plans through a Horsch Simba Pronto VR drill. In the heavy black grass areas she drills wheat and barley up to 50% more densely and out‐competes the black grass whilst in the more fertile areas pulling back on seed density. Overall average drilling rates of 250 seeds per square metre still apply but with pre mapped drilling variation according to soil conditions This VR drilling in conjunction with the N‐Sensor VR Nitrogen application across the farm, is producing consistently higher yields and avoiding much crop lodging. Into the future both Peter and Tamara have plans. Peter says that he would like to look at EM scanning of his land and re‐visit VR drilling as he feels that the technology both on the land and in the office will be easier to apply than it was when he experimented with it through Clive 20 years ago.

Tamara is going to follow in Peter’s footsteps by moving to direct drilling within the next 2 years. Prior to this she intends to have all the poor draining low lying land re –drained. When her grassland comes out of its 4 year lay she says they will not plough again but spray off and then direct drill from then on. She is planning on trialling a JD750, Cross Slot and Weaving direct drill over the next couple of seasons. Ultimately she would also like to move across to controlled traffic (CT) using two traffic plans – one for harvesting and one for everything else. She realises that this will be a big move, at present her 3 JD tractors use SF1 & 2 for guidance and steering, a move to a higher accuracy signal such as RTK will be necessary to implement these CT plans. Tamara and Peter are long standing clients of PD and as Tamara says;

“You get what you pay for along with any necessary professional help and advice from precision decisions”

If you want to benefit the industry leading soil sampling and scanning services as outlined below contact Precision Decisions on 01347 844132
Our soil sampling services have been designed to ensure maximum efficiency, traceability, and reliability. Using our own custom software gives us maximum flexibility in the services we provide, so that we can customise your sampling regime to meet your requirements. We offer many sampling services, for nutrients and for potato cyst nematode levels, and are
more than happy to personalise nutrient analysis to your exact needs. We also believe that soil sampling is more than just producing nutrient maps. Variable rate nutrient recommendations from FACTS qualified advisors are included in your sampling package, provided with machinery files for all major rate controllers, with no extra cost and advice whenever required.

Sampling processes
All our sampling orders start and progress through our online mapping portal, MiFarm. This enables you to place sampling orders with confidence, clearly identifying and naming your fields, and selecting those which require sampling.

The information entered in MiFarm is transmitted directly to the computer system operating in the sampling buggies. Our award‐winning software was developed in‐house and is entirely unique to us; its ‘optimised polygon’ technique ensures sample points are evenly distributed throughout the field. Every time the hydraulic sampling probe enters the soil, the positioning co‐ordinate is recorded, giving us complete records of exact sample locations, and you peace of mind that sampling is being carried out thoroughly and professionally. When a full sample has been collected automatic label printers issue a uniquely barcoded label with sample information printed on. As a sampling job is finished, the buggy software automatically updates the order status on MiFarm, keeping you up‐to‐date and informed, and alerts the lab to expect the samples,
increasing the efficiency of the process.

We have a very close working relationship with our laboratory partners which enables us to extend our traceability to include the time that samples are at the lab. Completion of a soil sampling order alerts the lab that samples will be delivered shortly, and thanks to our close links analysis results are available on MiFarm as soon as the lab releases them – you know
your results as soon as we do.

Mapping & recommendations
While results can be viewed on MiFarm when received, we also send paper and PDF copies of maps to you, and your agronomist if requested. Our sampling results are completely GateKeeper compatible and can be published directly to you. In addition, variable rate nutrient recommendations for the duration of your sampling regime are included, with no
further or future year charges.

Conductivity scanning provides a detailed map of the variation in soil properties across a field, the ideal base for making informed management decisions. Our non‐invasive EM scanning service collects data at a high rate for multiple parameters at two depths of soil, ensuring complete and comprehensive mapping of your fields.

Scanning process. Our scanner doesn’t require invasive contact with the ground, so scanning is not restricted to bare or ploughed fields. Soil moisture is an important element in creating detailed maps so autumn through to spring are ideal data collection periods. Because scanning is a one‐off process and an investment for future field management, we
collect a high density of data to create highly detailed maps:

  • Auto‐steered vehicles ensure collection in uniform swaths
  • Travelling between tramlines gives a representative scan of the field
  • Dual depth information provides an indication of soil changes through the profile – the scanner collects information to 40cm and to 130cm.
  • High data rate ensures we collect as much relevant data as possible; 11 parameters are recorded 8 times a second, giving a dense information set.
  • The combination of these factors means that the conductivity maps collected provide you with a reliable, digital, and detailed farming resource.

Using conductivity maps
Collecting the scanning data is only one step in utilising the sensor maps, and we believe our support in maximising your use of the data is a key part of this service. Conductivity maps can be used for a number of factors: to identify management areas, or yield potentials when used in combination with yield maps; to reduce soil sampling costs by identifying sampling targets; and to create variable rate seed maps which are not restricted to a limited number of discrete zones. Once scanning maps have been collected we work closely with our customers to integrate their knowledge of field characteristics into decision processes, as well as carefully considering other elements which may affect field performance – for example, the locations
of old field boundaries. Whether you want prescriptive maps creating for you, or training to create the maps yourself, we are committed to open data exchange and supportive service.


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