Table 2.

The mean water potential at which 50 % of hydraulic conductivity is lost (P₅₀), with standard error and replicates (n), determined from vulnerability curves using the 14, 27 and 42 cm diameter rotors, and the mean water potential at which 50 % of xylem water of released determined from native xylem water extraction curves using the 27 cm diameter rotor, with standard error and replicates (n), for five study species. Differences in P₅₀ among rotor sizes within each species are indicated by dissimilar letters (P < 0.05). The value of P₅₀ measured in the 14 cm diameter rotor for Pinus and Fagus could not be determined as curves were not run to completion due to the maximum rotational velocity of the rotor.

Species	Vulnerability curves			Extraction curves
	14 cm rotor	27 cm rotor	42 cm rotor	27 cm rotor
Pinus pinaster	–	−3.70 ± 0.06 (5)a	−3.50 ± 0.12 (5)a	−4.41 ± 0.05 (5)b
Populus nigra	−2.19 ± 0.10 (5)a	−2.32 ± 0.05 (9)a	−2.22 ± 0.10 (6)a	−2.84 ± 0.09 (5)b
Fagus sylvatica	–	−4.05 ± 0.05 (6)a	−4.01 ± 0.08 (5)a	−4.54 ± 0.08 (5)b
Prunus cerasifera	−4.31 ± 0.28 (10)a	−5.90 ± 0.06 (9)b	−5.95 ± 0.04 (6)b	−6.75 ± 0.05 (5)b
Eucalyptus sp.	−1.10 ± 0.13 (6)a	−2.07 ± 0.09 (4)b	−1.34 ± 0.24 (6)a,b	−4.76 ± 0.22 (5)c