Linked from
The 18 pages that link to Host plant, each with the reason it gives.
EpiphyteRelated: For an epiphyte, the host plant is a physical support rather than a food source.
Luna mothRelated: Luna moth caterpillars feed on leaves of several deciduous tree genera.
AcanthosomaRelated: Plant associations help describe the ecology of Acanthosoma species.
LasiocampidaeRelated: Identifying host plants helps explain where lasiocampid larvae feed and occur.
Leaf beetleRelated: Host plants determine where many leaf beetles feed, develop, and reproduce.
LepidopterologyRelated: Many caterpillars depend on particular plants for food and development.