Response of herbivore load and predator/prey ratio to nutrient manipulations.
Effects of press (solid line) and pulse (dashed line) treatments on herbivore load (A, B) and predator/prey ratio (C, D) at the CHNS and TUCK (means ±se). Effects within gray bars were not significantly different from zero, meaning that treatment and control plots did not differ. Herbivores consisted of all planthopper adults and nymphs plus Trigonotylus; predators consisted of all spiders. Asterisks indicate that pulse and press treatments had significantly different effects in a given year (α = 0.05).