Soil-carbon baseline sample -- the drip-converted block, an alfalfa & Sudan-grass farm on an IID lateral canal south of Calipatria, CA 92233

This farm block just converted from flood irrigation to pressure-compensating drip, but there is no soil-organic-carbon baseline recorded to measure whether the practice change is actually building soil health over time. Standard: USDA-NRCS soil-health assessment family (CPS 484 Mulching, infiltration/aggregate-stability field tests); SDG 15.3 Proof: core-sample photos at 3+ points + depth log + lab submission receipt + GPS Method (USDA-NRCS soil-health in-situ assessment, ~45-90 min): 1. Navigate to the plot; record GPS; sketch the sampling layout. 2. Photograph each sampling station. 3. Run the infiltration ring; record time to infiltrate 1 inch. 4. Assess aggregate stability and note visible organic matter, roots, and biology. 5. If compaction is in scope, record penetrometer resistance by depth. 6. Collect 0-15 cm cores if a lab subsample is specified; bag, label, complete COC. 7. Enter all measurements with units + depth, GPS, photos into the proof record; sign. Equipment: soil auger or trowel, infiltration ring + measured water + timer, penetrometer (if compaction in scope), clean bucket, sample bags + labels, gloves, GPS phone, camera Done when: Infiltration time recorded; Aggregate stability + organic-matter observation recorded; Each in-scope measurement recorded with units and depth; GPS waypoint + station photos + site sketch

Where

an alfalfa & Sudan-grass farm on an IID lateral canal south of Calipatria, CA 92233

Pay

$85 proposed

This packet is not funded yet, so this figure is a proposed price and not money waiting in escrow. If a buyer funds it, approved proof settles that price onchain. If nobody funds it, approved proof earns provable credit toward the work instead of cash. You see which before you claim, never after.

Proof

core-sample photos at 3+ points + depth log + lab submission receipt + GPS

This is exactly what gets it approved. Nothing settles without it.

Level

advanced

Open until

2026-09-03

How this work is done

A documented method, so this packet comes out the same whoever does it. Typically 60–120 minutes. Method of record: USDA-NRCS / COMET soil organic carbon baseline (stratified cores + bulk density, lab SOC by dry combustion)

Bring

• soil core sampler / auger
• bulk-density ring (known volume)
• depth tape / markers
• sample bags + labels
• GPS phone
• camera
• chain-of-custody + data sheet

Steps

1. 1. Confirm the field + management zone; record GPS; lay out stratified sampling points by soil type / slope position.
2. 2. At each point, take cores at defined depth increments (e.g., 0-10 and 10-30 cm); record each depth.
3. 3. Collect a known-volume bulk-density sample at each depth (needed to compute carbon per area).
4. 4. Composite same-depth cores per zone; bag, label, and complete chain-of-custody to the lab for SOC% by dry combustion.
5. 5. Photograph the site, a soil profile, and each sampling point; note land use and management history.
6. 6. Record the GPS grid, depths, bulk-density samples, COC number, and photos into the proof record; sign.

If it does not match the plan

• SOC% is lab-measured, not field-read -> mark result 'pending lab'; make NO on-site carbon claim.
• Very low SOC / bare compacted zones observed -> flag as priority for carbon-building practices.
• Do not claim a carbon credit or retirement from this baseline alone — it establishes a starting point for later re-measurement.

What counts as done

• Stratified cores at defined depths recorded per zone
• Bulk-density sample collected per depth increment
• Composited samples bagged + chain-of-custody to an accredited lab
• GPS grid + profile/point photos + management-history note

Proof is measured against these, not judged by taste.