Correlations were sought between insect species richness and abundance, and the chemical traits of foliage of 33 species of broad-leaved deciduous trees in southern Ontario. Number of Leipdopteran species collected by the Canadian Forest Insect Survey was not significantly correlated with any of the foliar traits after the effects of sampling intensity on species richness had been removed statistically. Relative abundance of Lepidopteran larvae was significantly related only negatively to the percentage of leaf dry mass as available carbohydrate. The distribution of four abundant, generalist moth species among host trees were considered in detail. Number of collections per host was associated with much of the distributional pattern for the fall webworm Hyphantria cunea and spotless webworm H. textor, whereas foliar traits were unimportant. Collecting effort was unrelated to relative abundance of the fall cankerworm Alsophila pometaria and linden looper Erannis tiliaria. For these latter two species relative abundance and a nutritional index, which includes nitrogen, water, lignin and polyphenol content of the leaves, were positively related. Our results suggest that general characteristics of communities of phytophagous insects on broad-leaved deciduous trees are not related to the levels of major nutrient components of the foliage.