Soil properties in log landings amended with subsoiling and biochar
| Authors: | William R. Rumpf, Morgan P. Davis, John M. Kabrick, John Stanovick, Lauren S. Pile Knapp, Deborah S. Page-Dumroese |
| Year: | 2026 |
| Type: | Scientific Journal |
| Station: | Rocky Mountain Research Station |
| DOI: | https://doi.org/10.1002/saj2.70257 |
| Source: | Soil Science Society of America Journal |
Abstract
Soils on log landings can be significantly degraded as a result of harvesting equipment. We evaluated the efficacy of biochar application and subsoiling to reduce compaction and improve soil properties. Fifteen log landings were selected across three US Midwest national forests: the Hoosier National Forest in Indiana, the Mark Twain National Forest in Missouri, and the Shawnee National Forest in Illinois. Landings were divided into four treatments: (1) biochar applied on the soil surface (22.4 Mg ha −1 ), (2) subsoiling (depth of 50 cm), (3) a combination of subsoiling and biochar (22.4 Mg ha −1 ), and (4) a control. Treatments were divided into split‐plots and were seeded with a competitive native seed mix or not seeded. Prior to treatment, soil bulk density was assessed (0–30 cm) to determine initial physical properties. Similarly, 1 year following treatments, soil samples were again collected from 0 to 30 cm to assess differences in soil properties among treatments. We found surface applications of biochar reduced bulk density by 18%–19% in the top 10 cm of soil regardless of seeding or when combined with subsoiling ( p < 0.05). Soils amended with biochar also saw a significant increase in potassium (K), and plant available phosphorus (P), as well as marginal increases in active carbon (C), total C, and nitrogen (N). When compared to pretreatment data, the bulk density decreased significantly ( p = 0.001) which may be attributed to the establishment vegetation and natural freeze thaw cycles.