Answers are grounded in this paper and cite their sources.
Barry N. Freeman, Robert R. Humphrey, The Effects of Nitrates and Phosphates upon Forage Production of a Southern Arizona Desert Grassland Range, Journal of Range Management, Vol. 9, No. 4 (Jul., 1956), pp. 176-180
No takes yet. Share an insight, caveat, or question.
Freeman et al. (1956) studied this question.
Synapse has enriched 5 related papers. Consider them for comparative context: