Growth, Water use and nutrient uptake from the subsoil by grass swards

• Published in: The Journal of agricultural science 1967-08, Vol.69 (1), p.125-130
• Main Authors: Garwood, E. A., Williams, T. B.
• Format: Article
• Language: English
• ISSN: 0021-8596; 1469-5146
• DOI: 10.1017/S002185960001652X

1. Plant nutrients, N, P and K, were applied to the soil surface or injected at a depth of 18 in. or 30 in. in perennial ryegrass swards, when the upper horizons of the soil profile were dry. 2. When the surface soil was dry and a soil water deficit of 2 in. existed there was no response to surface applied N but injection of N into moist soil at a depth of 18 in. produced a marked increase of growth. At this depth of injection there was a significant positive interaction between N and PK. 3. There was a substantial recovery in the herbage (59–80%) of the nitrogen applied to the subsoil, provided water was available in the soil horizon in which the nitrogen was applied. 4. Failure of a grass sward to regrow after cutting when the water available to the plant has been removed from the uppermost soil horizons is largely due to a deficiency of plant nutrients in the subsoil. The major deficiency is that of nitrogen.