Interactions between above- and belowground herbivores have been prominent in the field of aboveground-belowground ecology from the outset, although little is known about how climate change affects these organisms when they share the same plant. Additionally, the interactive effects of multiple factors associated with climate change such as elevated temperature (eT) and elevated atmospheric carbon dioxide (eCO2) are untested. We investigated how eT and eCO2 affected larval de