Increased Protection for Ecoregions Due to Prohibitions in Inventoried Roadless Areas
ecoregion	code #	outst.	increase in acreage attributable to roads allowed IRA(%)
Alaska Geographic Division
Northern Pacific Coast	23	X	34
Icefields and Tundra	104		41
Eastern Geographic Division
Western Great Lakes	7		12
New England/Acadia	12		44
Allegheny Highlands	15		8
Appalachian/Blue Ridge	16	X	53
Mixed Mesophytic	17	X	64
Central US Hardwoods	18		32
Ozark Mountains	19		64
Southeast Mixed Forests	22	X	49
Piney Woods	48		8
Middle Atlantic Coast	50		41
Southeastern Conifer	51	X	25
Florida Sand Pine Scrub	52	X	33
Northern Tall Grasslands	59		***
Western Geographic Division
North Central Rockies	30		52
Okanogan Forests	31		1420
Cascade Mnts. Leeward	32		13
North Cascades	33	X	7
Central Pacific Coastal	34	X	18
Central/South. Cascades	36		16
Eastern Cascades	37		90
Blue Mountains	38		42
Klamath-Siskiyou	39	X	28
Sierra Nevada	41	X	26
Great Basin Montane	42		132
South Central Rockies	43		76
Wasatch/Uinta Montane	44		249
Colorado Rockies	45		83
Arizona Mountains	46		34
Madrean Sky Islands	47	X	0
Palouse Grasslands	53		156
Montana Valley/Foothill	57		494
NW Mixed Grasslands	58		762
West. Short Grasslands	63		0
C. Cal. Shrub/Savanna	70	X	137
S. Cal. Woods/Shrub	71	X	46
S. Cal. Coastal Scrub	72	X	37
Snake/Col. Shrub Steppe	75		244
Grt. Basin Shrub Steppe	76		380
Wyoming Basin	77		901
Colorado Plateau	78		211
Mojave Desert	79		12
Sonoran Desert	80	X	10
Chihuahuan Desert	81	X	56
*** refers to values that are infinitely large since the demominator is zero