Soil health testimonial

Jim Thomson - Farm manager

Agrovista’s new Soil Health offer is proving its worth for Yorkshire farm manager Jim Thomson, confirming the success of his current soil improvement strategy and providing important pointers for the future.

Jim Thomson has been spent the past two decades in a quest to provide the ideal growing medium for his crops.

Over that time, soil health has become a passion as tight, lifeless earth evolved into fertile well-structured soil capable of supporting very high yields. 

Jim farms 220ha of arable cropping at H B Johnson & Co’s Danthorpe Hall near Hull, on Holderness series soils, which can range from sandy clay loam through to blue clay in the same field.

When he took on the manager’s role in the in mid 1990s he knew he faced an uphill battle to restore the soils.

“The farm was compacted beyond belief,” says Jim. “Cultivations were based on a plough-power harrow system and the fields hadn’t seen a subsoiler for years.” 

He gradually moved away from the plough to min till, while chopping and incorporating straw and bringing in vast quantities of organic manures and sludge cake.

“Slowly but surely we saw an improvement, with soils becoming easier to work and earthworms numbers increasing.

“I felt confident enough six years ago to buy a Sumo DTS and start strip tilling cereals and we’ve not looked back. In that time we have raised organic matter from an average of 1% to 4-5%.

“We’ve got to the stage that we want to leave soils as intact as possible. We usually do one or two passes with a Mzuri straw rake prior to drilling to manage residue and create seed-beds.

“As far as deeper cultivations are concerned, we dig hundreds of holes every year around the farm to check what’s going on and to see if and where we need to loosen, and to what extent.

“Over the years we’ve seen a huge reduction in compaction, and what we do have is much shallower and much less severe. So we must have been doing something right.”

When Jim’s agronomist, Tom Abbott, mentioned that Agrovista had launched a comprehensive soil health testing service, Jim jumped at the chance.

“Tom is not just my agronomist but an integral part of the farm business. He delivers a fantastic level of service, and I knew he wouldn’t offer it if he didn’t really believe in it.

“I saw Agrovista Soil Health as a great opportunity to check on how we were doing and whether our plans for the future were right.

“Soil is our biggest asset, but probably our most abused. Genetics and technology have moved on greatly in the past 40 years, but cultivations have not. Four tons an acre of wheat is still considered a good yield, as it was back then.”

The first full field test has thrown up a very encouraging result, scoring 78 points out of 100 (see panel below). Two further fields will be fully tested before drilling, and two to three fields from next year onwards, meaning a full test will be carried out every five to six years on each field.

“I think it is vital to get every field tested, especially on a farm like this where the soils are so variable and each field has a very different history,” says Jim.

“It’s been a fascinating exercise. I didn’t expect such a glowing report, but it is very satisfying to see we are on the right track. 

“Our farm average yield has increased by 0.5-0.75t/acre over the past 10 years. This season we achieved 4.77t/acre (11.78t/ha). But we’ve not just raised yields, they’ve become much more uniform. We no longer have good and bad fields, partly due to variable rate seed and fertiliser but mostly through our soil work. 

“The soil health check clearly illustrates this and is providing some very useful advice about how we can continue to improve our soils.

“It has also reinforced my decision to go further down the low-till route, investing a new subsoiler fitted with ultra-low disturbance legs and switching to a Horsch Sprinter so I can shallow right off when drilling, as well as using cover crops over winter or before wheat after vining peas to use roots to further enhance our soils. 

“I’d sum it up by saying this is a tremendous service, very comprehensive, and will really help me continue to improve our soils, yield and profitability over the coming years so we can achieve 95 points out of 100.

“It certainly ticks all the boxes for me, and I’d recommend it without hesitation.”

Agrovista Soil Health

Agrovista Soil health is a completely new way of operating, providing a picture of what’s happening in the soil physically, chemically and biologically, using a wide-ranging suite of measurements backed by expert interpretation and advice.

The first step is to assess soil characteristics. These include soil pH, organic matter, soil respiration levels to provide a good measure of microbial activity, C:N ratio to indicate decomposition rates and retention of applied manures, and cation exchange capacity to indicate nutrient holding ability. 

Soil textures and their capabilities are then assessed to help growers maintain structure, maximise water use efficiency and optimise porosity with the minimum of cultivations. 

Major and micro nutrient levels are then tested.

All this information is then ground truthed. A soil pit investigation reveals any compaction problems and show root mass and earthworm activity.

Soil aggregate size and soil stability are also recorded and comprehensive earthworm counts undertaken. Finally a machinery interface report is compiled indicating the suitability of operations and how best to manage them.

Fully-trained Agrovista staff then interpret all this information to provide simple but effective practical solutions to help growers manage their soils better.

Agrovista Soil Health score – Danthorpe Hall, Field 7

Soil Analysis 14/20
Spade pull-back 8/10
Soil pit and visual evaluation 9/10
Aggregate size, shape and distribution 8/10
Soil porosity 7/10
Soil stability 7/10
Soil infiltration 9/10
Manging machinery interface 7/10
Field soil heath score 78/100

Key findings:

  • pH – 6.8
  • OM – 4.1%
  • Soil respiration(mg/kg) ­– 115 (good)
  • C:N ratio – 10.4 (normal)
  • Cation exchange capacity – 21.5 (good)
  • Texture class – clay loam
  • Major nutrients at good levels
  • Micronutrients generally low
  • Spade pull-back (visual evaluation) – excellent soil structure
  • Good aggregate distribution, crumbles easily
  • Soil pit – no sign of horizontal barrier, significant root mass and earthworm activity
  • Soil stability – fairly good
  • Earthworm count – healthy population

Summary

  • Field generally in very good condition
  • Establish OSR with subsoil planter with low-disturbance leg set 15cm max to remove harvest traffic damage.
  • Could reduce depth if using berseem clover as companion plant
  • Ensure wetter areas in friable state before subsoiling – use LD points to prevent surface boiling
  • Consider seed dressing to aid establishment – important for stronger land
  • Apply early foliar manganese
  • Apply autumn and spring boron and molybdenum
  • Use regular tissue analysis
  • Continue to apply organic manures to target OM content of 5%, whilst maintaining C:N ratio to balance microbial activity for nutrient release from soil OM.

Download our Soil Health information sheet here.