Table I. Comparison of mean P_e and water potential associated with 50% loss of hydraulic conductance (P₅₀) values for leaves (n = 3) and stems (n = 3) of our eight sample Quercus species.

Values shown are means ± se (n = 3).

Species	Tissue	Trait
		Pe	P50
		MPa
Q. sadleriana	Leaf	−1.78 ± 0.08	−2.72 ± 0.25
	Stem	−1.17 ± 0.04	−2.74 ± 0.20
Q. garryana	Leaf	−1.70 ± 0.25	−2.81 ± 0.27
	Stem	−1.99 ± 0.35	−3.32 ± 0.56
Q. kelloggii	Leaf	−2.47 ± 0.18	−3.62 ± 0.13
	Stem	−3.28 ± 0.58	−4.73 ± 0.64
Q. lobata	Leaf	−2.4 ± 0.24	−3.02 ± 0.18
	Stem	−2.8 ± 0.40	−3.58 ± 0.25
Q. wislizenii	Leaf	−3.10 ± 0.29	−3.77 ± 0.13
	Stem	−3.35 ± 0.31	−4.10 ± 0.24
Q. agrifolia	Leaf	−2.89 ± 0.22	−4.47 ± 0.31
	Stem	−3.56 ± 0.19	−4.32 ± 0.26
Q. douglasii	Leaf	−3.13 ± 0.26	−4.45 ± 0.24
	Stem	−4.91 ± 0.3	−6.27 ± 0.06
Q. berberidifolia	Leaf	−3.74 ± 0.23	−5.52 ± 0.62
	Stem	−4.24 ± 0.18	−5.95 ± 0.38