| Soil Blend | Depth (inches) | Total Carbon % August 2018 | OM %* Aug 2018 | Total Carbon % August 2019 | OM % Aug 2019 | Total Carbon % August 2020 | OM % Aug 2020 |
| NC No compost | 0 - 8 | 3.5 | 6.2 | 2.9 | 5.0 | 3.7 | 6.7 |
| 8 - 16 | 2.6 | 5.2 | 2.5 | 4.0 |
|
| |
| 16 - 24 | 2.3 | 4.7 | 2.4 | 2.9 |
|
| |
| 5% | 0 - 8 | 4.0 | 7.2 | 4.0 | 6.2 | 6.3 | 9.8 |
| 8 - 16 | 2.6 | 4.7 | 3.2 | 4.2 |
|
| |
| 16 - 24 | 2.6 | 4.4 | 3.1 | 3.8 |
|
| |
| 10% | 0 - 8 | 4.6 | 7.6 | 4.8 | 7.4 | 8.5 | 14.3 |
| 8 - 16 | 2.4 | 4.3 | 3.8 | 5.4 |
|
| |
| 16 - 24 | 2.7 | 4.5 | 2.7 | 3.6 |
|
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