Soil fertility changes under long-term seeding
Schoenau, J.J., R. Bolton and C. Baan. 2009. SSCA
Abstract
One of the most profound effects of adopting minimum disturbance direct seeding is the
development of a surface residue layer. The surface residue, a.k.a. thatch or duff layer
accumulates due to the addition of organic material to the soil surface and lack of incorporation.
Without incorporation, decomposition is reduced (Schoenau and Campbell, 1996). Similarities
exist between the no-till system and native grasslands. In native grasslands, above ground
vegetation develops, matures, dies and forms a layer on the surface of the soil. Nearly thirty
years ago, Doran (1980) noted that the no-till ecosystem has similarity to other undisturbed
ecosystems such as native grassland, with levels of carbon, nitrogen and water that are higher
than tilled land.
