Floridian Coastal Plain
Southeast
11
FL
SE
NA
East
Coastal Gulf Plains
AL, FL, LA, MS
Southeastern Coastal Plain
AL, FL, GA, SC
Gulf Plains
AL, GA, MS, TN
Eastern Coastal Plain
GA, NC, SC
NE
Western Gulf Plains
South Central
7
TX
SC
Mississippi Delta
LA, MS
Edwards Plateau
Chihuahuan Desert
NM, TX
West
Ouachita Hills
ArKS, LA, OK, TX
Southeastern Great Plains
KS, OK, TX
Mississippi Alluvial Plains
ArKS, IL, KY, LA, MS, MO, TN
Southern Great Plains
CO, KS, NM, OK
Ozark Highlands
ArKS, IL, KS, MO, OK, TX
Southern Piedmont
Southern Appalachians
9
AL, GA, NC, SC
Cumberland Highlands
AL, GA, TN
Southern Appalachia
GA, NC, SC, TN, VA, WV
Northeastern Piedmont
NC, SC, VA
Appalachia
KY, OH, TN, VA, WV
Appalachia Bluegrass Hills
ArKS, IL, IN, KY, MO, OH, TN
Rio Grande Basin
Southwest
5
AZ, NM, TX
SW
Sonoran Desert
CA, AZ
Mogollon Rim
NV, AZ, NM
Navajo Plateau
AZ, NM, UT, CO
Great Plains Tablelands
CO, NM, OK, TX
Colorado Plateau
UT, CO, AZ, WY
Southern Rocky Mountains
NM, WY, CO
Death Valley Basin
Great Basin
4
CA, NV, UT, AZ
PS
Eastern Great Basin
ID, NV, UT
Utah High Plateaus
UT, ID, WY
Western Great Basin
NV, CA
Snake River Plain
OR, ID, NV, WY
PN
Southern California Coastal Range
California
3
CA
California Central Valley
Sierra Nevada Mountain Range
CA, NV
Northern California Coastal Range
CA, OR
Till Plains
Northern Plains
6
IL, IA, KS, MO, OK
Western Great Plains
CO, KS, NB, WY
Eastern Great Plains
IA, KS, MO, NB, OK, SD,
Western Till Plains
IL, IA, KS, MN, MO, NB, WS
Sandhills
NB, SD, WY
NC
Prairie Coteau Lands
IA, MN, NB, ND, SD
Northern Great Plains
MN, ND
Northwestern Great Plains
MT, ND, SD
Chesapeake Bay
Northeast
10
DE, DC, MD, NJ, NY, NC, PA, VA
Northern Appalachia
MD, PA, VA, WV
Finger Lakes
NY, PA
Connecticut River Basin and Highlands
CT, MA, NH, NJ, NY, RI, VT
Northeastern Highlands
NJ, NY, PA, VT
The North Woods
ME, NH, NY, VT
Eastern Till Plains
Great Lakes
8
IN, MI, OH
Central Till Plains
IL, IN, IA, KY, MI, MO, WI
Allegheny Plateau
OH, PA, WV
Central Great Lakes Uplands
IL, IA, MI, MN, WI
Great Lakes Plains
IN, MI, OH, WI
Northern Lake Country
MI, MN, WS
Wyoming Basin
Northern & Central Rockies
2
MT, WY, CO, ID, UT
Middle Rocky Mountains
ID, MT, WY
Wyoming Highlands
MT, NB, ND, SD, WY
Missouri River Plateau
MT
Northern Rocky Mountains
ID, MT
Northwestern Rocky Mountains
ID, MT, WA
Blue Mountain Region of the Columbia Plateau
Northwest
1
NV, OR, WA, ID, CA
Cascade Mountain Range
CA, OR, NV
Oregon Coastal Range
OR
Grande Coulee Basin of the Columbia Plateau
WA, OR, ID
Northern Cascades
WA