U. S. DEPARTMENT OP AGRICULTURE 
CLIMATIC PROVINCES AND PLANT GROWTH REGIONS OF THE UNITED STATES 
Figure 2 
SOIL CONSERVATION SERVICE 
75° 73° 
Scale in Miles 
I t I Wet, Mesothermal, Adequate at all seasons. 
I a I Wet, Microthermal, Adequate at all seasons. 
I' 3 I Humid, Tropical, Adequate at all seasons. 
ft ■* I Humid, Mesothermal, Adequate at all seasons. 
I s I Humid, Microthermal, Adequate at all seasons. 
I e ;| Humid, Mesothermal, Summer deficiency 
I 7 I Humid, Microthermal, Summer deficiency. 
I a I Subhumid, Mesothermal, Adequate at all seasons. 
I o I Subhumid, Microthermal, Adequate at all seasons. 
I IP I Subhumid, Mesothermal, Summer deficiency. 
LEGEND FOR CLIMATIC PROVINCES 
" I Subhumid, Microthermal, Summer deficiency. 
« I Subhumid, Tropical, Deficiency at all seasons. 
'3 I Subhumid, Mesothermal, Deficiency at all seasons. 
I Subhumid, Microthermal, Deficiency at all seasons. 
IS I Semiarid, Mesothermal, Summer deficiency. 
I^Ptg^l Semiarid, Microthermal, Summer deficiency. 
I 17 I Semiarid, Mesothermal, Dericiency at all seasons. 
I IB I Semiarid, Microthermal, Deficiency at all seasons. 
I t» I Arid, Tropical, Deficiency at all seasons. 
Arid, Mesothermal, Deficiency at all seasons. 
Arid, Microthermal, deficiency at all seasons. 
I 23 "1 Tundra. 
LEGEND FOR PLANT GROWTH REGIONS 
I North Pacific Coast. 
2 Willamette Valley-- Puget Sound. 
3 Central California Valleys. 
4 Cascade - Sierra Nevada. 
5 Southern California. 
6 Columbia River Valley. 
7 Palouse - Bitterroot Valley. 
8 Snake River Plain • Utah Valley 
^ 9 Great Basin - Intermontane. 
CTL 10 Southwestern Desert. 
I I Southern Plateau. 
12 Northern Rocky Mountains. 
II 1 1 1 1 l l 13 Central Rocky Mountains 
14 Southern Rocky Mountains. 
I 1 15 Northern Great Plains. 
16 Central Great Plains. 
\'//'A 17 Southern Plains. 
1 8 Northern Black Soils. 
I-H- t-fl 19 Central Black Soils. 
PS:\<-1 20 Southern Black Soils. 
21 Northern Prairies. 
t^>S^ 22 Central Prairies. 
EH] 23 Western Great Lakes. 
II I I I 24 Central Great LaKes. 
OTD 25 Ozark -Ohio -Tennessee River Valleys 
26 Northern Great Lakes -St. Lawrence. 
Appalachian. 
W7\ 28 Piedmont. 
Eia 29 Upper Coastal Plain. 
30 Swampy Coastal Plain. 
31 South -Central Florida. 
32 Subtropical Florida. 
Plant growth Regions by Furman Uoyd \ 
I by Cartographic Drafting Unit 
