Table 1.

List of species included in this study with the representation of individual species in refugia by broad regions to aid interpretation of figure 1. (A detailed breakdown for regions exactly corresponding to figure 1 is provided in the electronic supplementary material, table S2. NC, northern coastal refugia including Alaska, Haida Gwaii and Vancouver Island in figure 1; SC, mesic southern coastal areas including California coast, Klamath Mtns, Sierra Nevada and the s. California Mtns in figure 1; NIB, northern interior basins with subalpine conditions including the Columbia Plateau, Northern Basins, Snake River Plains and Wyoming Basin; SIH, southern interior highlands with xeric conditions including Arizona Mountains, Colorado Plateau, Central Basin, New Mexico Plateau and southwest Tablelands; HP, high plains with boreal conditions; SM, Sierra Madre with mesic and subalpine climate equivalent.)

		location of refugia by species (% of total species refugia)
no.	species	NC	SC	NIB	SIH	HP	SM
1	Abies amabilis	23	45	26	1	0	5
2	Abies lasiocarpa	12	8	45	27	7	1
3	Abies procera	0	90	0	3	0	7
4	Acer macrophyllum	0	88	0	0	0	12
5	Alnus rubra	0	89	0	3	0	8
6	Calocedrus decurrens	0	76	1	6	0	17
7	Cupressus nootkatensis	44	45	0	0	0	11
8	Larix occidentalis	0	29	1	58	0	12
9	Picea engelmannii	6	4	10	70	8	2
10	Picea glauca	33	0	2	18	47	0
11	Picea mariana	53	0	1	2	44	0
12	Picea sitchensis	13	76	1	2	1	7
13	Pinus albicaulis	3	25	47	22	3	0
14	Pinus contorta	15	28	17	30	9	1
15	Pinus edulis	0	3	0	46	0	51
16	Pinus monticola	0	80	9	6	0	5
17	Pinus ponderosa	0	26	0	56	2	16
18	Populus tremuloides	5	3	4	64	20	4
19	Pseudotsuga menziesii	0	46	5	35	3	11
20	Thuja plicata	13	63	0	15	0	9
21	Tsuga heterophylla	16	65	8	2	0	9
22	Tsuga mertensiana	3	91	1	2	0	3