Tilling or disking soil can provide both benefits as well as drawbacks to a restoration site. For example, tilling can help seedling establishment by aerating the soil, creating microsite heterogeneity and enhance microbial activity [1]. Seeds scattered on tilled soil are also less likely to blow away. However, tilling also creates disturbance that can facilitate invasion, lead to soil compaction elsewhere when moving around machinery used for tillage, and often results in soil carbon loss. Disking can also result in deep furrows that subsequently bury seeds too deeply [2]. Tilling might be a good approach to employ for toxic soils and poorly drained soils [3]. If you are planning on tilling, till to a depth between 6 and 12 inches.
Resources
- Prepare Your Soil (Tillage Methods on a Small Farm)
- No-Till Farming Pros and Cons – Mother Earth News
- Tilling & Scarification | Colorado State Forest Service
References
[1] Wang X, Bartha R. Effects of bioremediation on residues, activity and toxicity in soil contaminated by fuel spills. Soil Biology and Biochemistry. 1990 [accessed 2022 Dec 22];22(4):501–505. https://www.sciencedirect.com/science/article/pii/0038071790901853. doi:10.1016/0038-0717(90)90185-3
[2] McCoy JW, Keeland BD, Lockhart BR, Dean T. Preplanting treatments and natural invasion of tree species onto former agricultural fields at the Tensas River National Wildlife Refuge, Louisiana. Asheville (NC): U.S. Department of Agriculture, Forest Service, Southern Research Station.; 2002. p. 405–411. General Technical Report No.: SRS-48. p. 405–411. https://www.fs.usda.gov/research/treesearch/4850
[3] Rochette P. No-till only increases N2O emissions in poorly-aerated soils. Soil and Tillage Research. 2008 [accessed 2022 Dec 22];101(1):97–100. https://www.sciencedirect.com/science/article/pii/S016719870800113X. doi:10.1016/j.still.2008.07.011