Table I. Results from model simulations testing the impacts on leaf hydraulic vulnerability of declines in conductivity in the xylem and outside-xylem pathways.

For each set of simulations, we present R_ox, xylem P₅₀ and outside-xylem P₅₀, K_max, Ψ_leaf at leaf P₅₀ and leaf P₈₀, P_xylem at leaf P₅₀, and the initial slope of the leaf hydraulic vulnerability curve (at −0.1 MPa), obtained from the logistic function , which was selected as the maximum likelihood model in all simulations (compare with Supplemental Table S1).

		Input Conditions				Output of Leaf-Level Responses
Scenario	Simulations	Rox	Xylem P50	Outside-Xylem P50	Kmax	Leaf P50	Leaf P80	Pxylem at P50	Initial Slope
		%	MPa		mmol m−2 s−1 MPa−1	MPa			mmol m−2 s−1 MPa−2
Rox > Rx	Low vulnerability for xylem and outside-xylem components	74	−1.00	−1.00	8.62	−5.50	−11.6	−0.74	−0.09
	High vulnerability for only the outside-xylem component	76	−1.00	−0.25	7.56	−2.37	−7.78	−0.28	−2.08
	High vulnerability for only the xylem component	71	−0.25	−1.00	8.18	−1.53	−2.72	−0.32	−0.28
	High vulnerability for xylem and outside-xylem components	74	−0.25	−0.25	7.26	−1.48	−3.83	−0.25	−1.97
Rx > Rox	Low vulnerability for xylem and outside-xylem components	39	−1.00	−1.00	9.03	−2.49	−5.03	−0.78	−0.32
	High vulnerability for only the outside-xylem component	42	−1.00	−0.25	8.32	−1.23	−3.92	−0.35	−4.50
	High vulnerability for only the xylem component	36	−0.25	−1.00	8.02	−0.83	−1.78	−0.39	−3.06
	High vulnerability for xylem and outside-xylem components	39	−0.25	−0.25	7.65	−0.68	−1.75	−0.30	−6.02