Why some of our protocols are changing

Why some of our protocols are changing 792 498 Soilmentor

Why we’re changing some of our protocols

We’re making some small changes to some of our scoring and protocols alongside the launch of the Regen Platform. Each of these changes have been made alongside Nicole Masters and the team at Integrity Soils, to ensure collecting soil health data on your farm feels clear and repeatable over time. We’ve detailed each of these changes below for your reference.

The Slake Test

Previously, our slake test protocol had a scoring of 8 options, with a method involving moving a sieve to disturb soil and evaluate its resilience across several steps.

We’ve decided to simplify this scoring, so you now rate your soil lumps as one of five options, after five minutes submerged underwater. We think this method will make your results easier to repeat over time, and will make the test easier to carry out. See the new scoring explained further here.

If you have recorded your soil previously from 1-8 in the slake test, your historical results will be moved into the new 5 option scoring, and your old 1-8 score will be kept as a note in Soilmentor, so you can still refer back to it. You’ll be able to see how your soil results score on the Regen Platform right away in the new scoring.

Basal Ground Cover Transect (% Bare Earth)

We’re changing the way we think about ground cover, from previous ‘% Bare Earth’ monitoring using a quadrat to estimate the proportion of foliar cover, to basal cover, which examines the total area of the earth covered by plants extending into the soil, rather than only covered by leaves or foliage (see image below).

Our new ‘Basal ground cover transect’ metric in Soilmentor will feed into the Regen Platform as one of our Regen Indicators. This new ground cover testing protocol involves moving away from a sample site in a transect line, sticking a fence post or stick into the ground as you go, and recording what the base of your post touches as it goes into the soil (read more on this method here). Basal cover is a more reliable measure year to year, and is a better indication of your soil’s resilience to erosion than foliar cover.

If you’ve already recorded ‘% Bare Earth’ in Soilmentor with a quadrat, we’ll display your previous percentage cover scores in the Regen Platform for your reference in the meantime, and we encourage you to update them with a basal ground cover transect when you get the time!

Image from University of Idaho page explaining different types of cover – read more here.

Infiltration Rate

We’ve pulled out the infiltration rate test into two different tests to record in the Soilmentor app, called ‘Infiltration rate – 1st inch‘, and ‘Infiltration rate – 2nd inch‘.

This is a small change we’ve made to ensure that the Regen Platform can benchmark your results accurately. The ‘2nd inch’ infiltration rate is one of our Regen Indicators, as research shows that a second infiltration rate done immediately after the first is a much more accurate representation of your soil’s infiltration. The Regen Platform will only display a result from this second infiltration rate activity recorded in the app.

If you don’t intend on using the Regen Platform, you can continue doing your infiltration rates normally – your historical data will all be saved in the ‘1st inch’ test.

The Brix Barometer

We’ve split out brix testing in Soilmentor into ‘Brix of grass or crops’ and ‘Brix of weeds’, to allow for the calculation of one of our new Regen Indicators – the ‘Brix Barometer’. This new combined metric looks at the difference between brix readings of a weed or undesirable plant, and brix readings of your grass in a pasture, or your crop. 

Brix measures the light refracting through dissolved sugars with a refractometer, showing the nutrient density levels of a plant, based on the presence of a diversity of simple and complex sugars. If the brix of the weeds on your farm is higher than the brix of your grasses or crops, this indicates that your soil is a better environment for weeds than for crops – probably due to compaction or a microbial imbalance. If the brix of your crops is higher than the brix of weeds, you likely don’t need to take any action to manage ‘weed’ species. 

Nodulation of Legumes

We’ve split out the scoring of the ‘Nodulation of legumes’ test into more categories. Our new scoring allows for more precise results, and will feed into the Regen Platform as one of our Regen Indicators. Historic data will be moved into the new scoring in Soilmentor. 

Read our new scoring for legume nodulation here

Rooting depth (80%)

We’ve added a new rooting depth test, ‘Rooting depth (80%)’, which measures the depth at which the majority (approximately 80%) of plant roots are penetrating, and is one of our Regen Indicators. 

This new test takes into account that there may be a few ‘outlier’ roots which have managed to grow deeper, but do not necessarily indicate the soil’s condition for root growth. Conditions which limit root growth include compaction, changes in salinity / pH, low oxygen levels, or nutrient deficiencies.

Historical rooting depths will remain in the ‘Rooting depth (Total)’ test in Soilmentor, so if you want to analyse your rooting depths on the Regen Platform, you’ll need to go out and record some new 80% rooting depths, by following these instructions

The Regen Platform will be launching in January 2022. For the full list of Regen Indicators, head to our soil test page here. If you’re already a Soilmentor customer, you will be able to upgrade your subscription to access the Regen Platform once we launch.  Stay tuned for more info!