Table 1. Herbivores and plants used in this study.

Herbivore—plant pairings used in feeding assays. Species marked with (I) are introduced species; common names are given in parentheses. Below each species name, we have listed the order and family of each species.

Herbivore species	Herbivore diet	Plant species
Unidentified tortricid (Lepidoptera, tortricidae)	Specialist	Lindera benzoin (northern spicebush)
Arge scapularis (elm argid sawfly) (Hymenoptera, argidae)	Specialist	Ulmus rubra (slippery elm)
Atteva aurea (ailanthus webworm) (Lepidoptera, yponomeutidae)	Specialist	Ailanthus altissima (tree-of-heaven) (I)
Chrysochus auratus (dogbane beetle) (Coleoptera, chrysomelidae)	Specialist	Apocynum cannabinum (dogbane)
Danaus plexippus (monarch butterfly) (Lepidoptera, nymphalidae)	Specialist	Asclepias syriaca (common milkweed)
Epimecis hortaria (tulip tree beauty) (Lepidoptera, geometridae)	Generalist	Lindera benzoin (northern spicebush) Liriodendron tulipifera (tulip poplar) Sassafras albidum (sassafras)
Euchaetes egle (milkweed tussock moth) (Lepidoptera, arctiidae)	Specialist	Apocynum cannabinum (dogbane) Asclepias syriaca (common milkweed)
Hyphantria cunea (fall webworm) (Lepidoptera, arctiidae)	Generalist	Acer negundo (box elder) Liquidambar styraciflua (sweetgum)
Malacosoma americanum (eastern tent caterpillar) (Lepidoptera, lasiocampidae)	Generalist	Prunus serotina (black cherry)
Melanophia canadaria (canadian melanophia) (Lepidoptera, geometridae)	Generalist	Acer negundo (box elder) Lindera benzoin (northern spicebush) Sassafras albidum (sassafras)
Nematus tibialis (locust sawfly) (Hymenoptera, tenthredinidae)	Specialist	Robinia pseudoacacia (black locust)
Papilio polyxenes (black swallowtail) (Lepidoptera, papilionidae)	Specialist	Foeniculum vulgare (fennel)
Papilio troilus (spicebush swallowtail) (Lepidoptera, papilionidae)	Specialist	Lindera benzoin (northern spicebush) Sassafras albidum (sassafras)
Saucrobotys futilalis (dogbane webworm) (Lepidoptera, crambidae)	Specialist	Apocynum cannabinum (dogbane)