1 The generalization that ferns are under-utilized by phytophagous insects in comparison to angiosperms may be invalid because of biases involving plant growth form, plant range, and unequal sampling efforts.
2 Comparison of nineteen fern species with 652 herb species, the angjosperm growth form most similar to the ferns, indicates no significant difference in the mean number of supported macrolepidopteran species. When the herbs are subdivided into annuals, biennials and perennials, only the annual herbs are significantly different than the ferns.
3 Comparisons of the occurrence distributions for ferns and the herb categories also demonstrate that only the annual herbs support more macrolepidopteran species than the ferns. The same results are obtained when random assemblages of herbs are created that are the same size as the fern assemblage.
4 Both the occurrence distributions and the species?area relationship for the ferns indicate that host records for insects feeding on ferns may be grossly incomplete.
5 The similarity of exploitation of ferns and perennial herbs by the Macro-lepidoptera suggests that other foliage feeding insects may also use ferns at levels equivalent to angiosperms.