Table 1. Diversity effect on growth and herbivore damage.

	Plant height		Damage by H. grandella
a) Genotypic diversity	F1,218	P	F1,218	P
Diversity	1.03	0.311	1.47	0.226
b) Species diversity	F1,166	P	F1,167	P
Diversity	0.04	0.849	0.90	0.344

Summary of results from generalized linear mixed models testing for the effects of (a) big-leaf mahogany (Swietenia macrophylla King, Meliaceae) genotypic diversity and (b) tree species diversity on mahogany growth and damage by the specialist Hypsipyla grandella (number of attack sites per plant). We tested the effect of mahogany genotypic diversity by comparing genotypic monocultures to genotypic polycultures, whereas to test for a species diversity effect we compared genotypic monocultures and species polycultures. F-values and associated significance levels (P) are shown, as well as numerator and denominator degrees of freedom (subscripts).