The Cohesion-Tension theory

In the June 2004 (162: 3) issue of New Phytologist, U. Zimmermann et al. published a Tansley review that criticizes the work of many scientists involved in the study of long-distance water transport in plants (Zimmermann et al., 2004). Specifically, the review attempts to 'show that the arguments of the proponents of the Cohesion Theory are completely misleading'. We, the undersigned, believe that this review is misleading in its discussion of the many recent papers which demonstrate that the fundamentals of the Cohesion-Tension theory remain valid (Holbrook et al., 1995; Pockman et al., 1995; Steudle, 1995; Milburn, 1996; Sperry et al., 1996; Tyree, 1997; Melcher et al., 1998; Comstock, 1999; Stiller & Sperry, 1999; Tyree, 1999; Wei et al., 1999a; Wei et al., 1999b; Cochard et al., 2000; Cochard et al., 2001a; Cochard et al., 2001b; Richter, 2001; Steudle, 2001; Cochard, 2002; Tyree & Zimmermann, 2002; Tyree, 2003; Tyree & Cochard, 2003; Tyree et al., 2003). We wish the readers of New Phytologist to know that the Cohesion-Tension theory is widely supported as the only theory consistent with the preponderance of data on water transport in plants.