Which fields should I test?


Hi everyone,

How did you decide which fields to do soil tests on?

Thanks @nielscorfield for the advice on the website, it is really helpful for choosing!
—> https://soils.sectormentor.com/soil-tests/which-fields-should-i-monitor/

I’m about to get started with testing the soils on my Dad’s conventional small mixed farm in Oxfordshire. Our soil is silty clay loam - it varies a bit over the farm, but generally gets more silty in the valley by the brook.

After chatting with Dad we’ve decided on 6 fields which could be interesting. However they’re all a bit more complex than just a field, there’s varying soil types, half this and half that, and all quite big!

—> Long Field (20ha): A lot of soil variance, from ironstone outcrop at the top of the hill to heavy ground in a dip to lighter ground by a small area of woodland, also a very wet corner and southern end is heavy wet bank. Currently planted with winter wheat, previously oilseed rape. Could probably do about 5 different sample sites on this field alone!

—> Field Cottage Field (11.8ha): One side previously pasture for 5+ years, the other side pasture for 18 years, now both winter wheat.

—> Brook Field (8ha): Arable rotation for 9 years - now winter wheat, previously oil seed rape.

—> Main Road Field (18ha): Partially fallow stubble as part of mid tier env scheme, partially ploughed - this area will be spring barley for Budweiser to malt. Previously winter wheat.

  • Drive Field (12.4ha) Permanent pasture 100 years+ - old ridge and furrow field, site of a medieval village

  • Oak Tree Field (9ha): On arable rotation, previously winter wheat, then spring oats under sown with grass, now pasture grazed by cattle pre November, now sheep.

My instinct is to go for:

Oak Tree Field
Drive Field
Brook Field
Field Cottage Field, both sides

Think the Long Field and Main Road Field will be too complicated for now.

Any advice on this topic from those who are already testing would be much appreciated!

Annie :slight_smile:

Field Cottage Field:

Field Cottage Field and Brook Field:



Good work.
Sounds like the variation in fields would be a bit of a headache (one argument for changing the field boundaries in the future). Might also be worth having some variable analysis done on the farm as well. Like satellite NDVI. This is very cheap and will show where the changes are more exactly in the field. For ref.
In the end, just picking a few and having a go is going to tell you a lot anyway. Even if it’s to then review which fields you continue with.
Does sound like a big area. You got a quad or 4x4 to help the work?

Nice one,


Thanks @nielscorfield! The complex field lay out is actually down to two infrastructural changes on the farm - Field Cottage Field was split in two by a new road way going down to the solar panels in the bottom of the valley. Same thing happened on the Main Road Field but it was a water pipe being built by the council - this will soon be covered over again but it’s been like that for over two years so the field has been cultivated in two parts for two growing seasons… I should talk to dad about redefining them. :grinning:

We’ve got a Landrover Defender which dad uses to get around so we will use it when the time comes - I didn’t start the soil testing on my last visit because the ground was very frozen. Hoping to get back there again in a few weeks to get going. So far have found the SM4S set up very easy, and it’s good to have a little time to think about which fields before we actually dig in - let the weather warm up just a little over the next few weeks!

Speak soon,


@nielscorfield @annie.landless one thing I was discussing with a soils researcher the other day was whether it make sense to do soil sampling at the worst and best parts of each field. We all have some understanding of the best and worst parts of each field, so by doing measurements in these specific areas the difference between the two could highlight underlying issues in the field. What do you think? Do most other farmers feel like they would be interested in doing soil tests in the best and worst parts within a field?


I think this depends a few things
Firstly, is the field being managed as one? Or if not, how is/or can the split be managed separately?
If the former there’s not much point taking separate measurements. The average that is generated from having the low or high readings included will give a more accurate picture of the whole.
It will also keep the data under control. That said, if there’s opportunities to- or existing maps of variability in field then they should def be brought to bare in the decision making. I’m thinking of NDVI or soil texture grid maps, the latter may be extrapolated from the first/