Effects of applications of fungicide, phosphorus and nitrogen on the structure and productivity of an annual serpentine plant community

Benomyl and phosphate were applied to patches of 2 annual serpentine communities dominated by forbs. After 1 yr neither Benomyl nor phosphate had affected plant productivity (except for legume productivity which was increased by P application), the abundance of any species or mycorrhizal infection, but Benomyl decreased P concentration in shoots whereas added P increased its concentration. At 1 site, added phosphorus also increased N concentration in the shoot. In the following year, N was added. Both N and P applications decreased the abundance and total above-ground dry weight per unit area of Plantago erecta, a dominant annual forb, and decreased the density of all plants taken together. Additionally, Benomyl increased total plant density. Phosphorus and N increased productivity of the whole community. -from Authors