 The other six pots remained well watered and weren't exposed to mannitol.After adding mannitol to the soil of Pot A, that plant 1's stomata closed within fifteen minutes even though half its roots remained in the well-watered soil of Pot B. Novoplansky's team collected stomatal aperture data using epidermal impressions.This result wasn't surprising, since stomatal closing as a drought response has been widely studied; in this response, Abscisic Acid (ABA) is produced in the roots and sent up to leaves to close the stomates.