2.4 Leaf surface wettability
Three fresh leaves per species were carefully excised from the plants and used as replicates. For each species, the area of interest (seeTable 2 ) was isolated using a scalpel so that it would lie as flat as possible on the stage. Leaf surface wettability was assessed by measuring the contact angle (θC) in a tensiometer fitted with a high-speed camera (Attension Theta optical tensiometer, Biolin Scientific AB), using the sessile drop method. A 5 μl droplet of dH2O (as suggested by Matos and Rosado 2016) was placed on the leaf surface by the tensiometer and the θC was recorded for 10 seconds (14 FPS). The resulting static θC was measured using the Young-Laplace fit.