1. Latex functions as a physical and chemical defence against herbivoresthat may vary in their responses to latex quantity and chemical composition. Intheir introduced ranges, many exotic plants experience reduced herbivore regulation,especially from specialist herbivores, which may lead to differences in defences amongnative and invasive populations.

　　2. Here, we compared latex produced by seedlings from native and invasivepopulations of tallow tree (Triadica sebifera) when damaged by a native specialistor generalist caterpillar.

　　3. We measured the growth of caterpillars fed leaves of plants from native andinvasive populations that had latex washed from the leaves or were unwashed controls.

　　4. We found that constitutive latex mass, tannins and flavonoids of plants frominvasive and native populations were similar. The masses of caterpillars fed leavesfrom native and invasive populations were comparable regardless of leaf washing.

　　5. We also found that the specialist induced more latex production than the generalistdid, especially for plants from invasive populations. Tannins increased and flavonoidsdecreased when plants were damaged by the generalist caterpillar but neither changed when plants were damaged by the specialist caterpillar.

　　6. Our results suggest divergent selection on the physical and chemical propertiesof latex in the introduced range. The quantity of latex produced was more sensitiveto herbivore identity in the introduced range but the specificity of the latex chemicalresponse was retained.