Fig. 3. Different apparati for measuring physical strength of leaves. Diagrammatic representation of the devices used for (a) tearing tests, as described in Hendry and Grime (1993); (b) scissoring test (prototype model from Darvell et al. 1996; a very similar device is described in Wright and Illius 1995); (c) shearing tests reproduced from Wright and Cannon (2001) (safety guard, quick-release sample holder and electronic control unit not shown); and (d) punch tests, from Aranwela et al. (1999).