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Wetlands of the United States

Their Extent and Their Value To Waterfowl and Other Wildlife

Contributions to Other Wildlife

Table 5

Table 5. --Description and acreage of wetland types in the United States

Wetland category and type	Water depth ¹	Total acres
INLAND FRESH AREAS:
1. Seasonally flooded basins or flats	Few inches in upland; few feet along rivers	23,092,000
2. Inland fresh meadows	Few inches after heavy rains	7,518,000
3. Inland shallow fresh marshes	Up to 6 inches	3,969,000
4. Inland deep fresh marshes	Up to 3 feet	2,346,000
5. Inland open fresh water	Up to 10 feet; marshy border may be present	2,596,000
6. Shrub swamps	Up to 6 inches	3,813,000
7. Wooded swamps	Up to 1 foot	16,809,000
8. Bogs	Shallow ponds may be present	3,347,000
INLAND SALINE AREAS:
9. Inland saline flats	Few inches after heavy rain	1,064,000
10. Inland saline marshes	Up to 2 feet	272,000
11. Inland open saline water	Up to 10 feet; marshy border	282,000
COASTAL FRESH AREAS:
12. Coastal shallow fresh marshes	Up to 6 inches at high tide	2,213,000
13. Coastal deep fresh marshes	Up to 3 feet at high tide	1,631,000
14. Coastal open fresh water	Up to 10 feet; marshy border often present	197,000
COASTAL SALINE AREAS:
15. Coastal salt flats	May have few inches at high tide	423,000
16. Coastal salt meadows	May have few inches at high tide	956,000
17. Irregularly flooded salt marshes	Few inches at wind tide	698,000
18. Regularly flooded salt marshes	Up to 1 foot at high tide	1,576,000
19. Sounds and bays	Up to 10 feet at high tide	1,114,000
20. Mangrove swamps	Up to 2 feet	523,000
¹Refers to average conditions during growing season except for Type 1. In Type 1 bottomlands, flooding ordinarily occurs in late fall, winter, or spring. In Type 1 upland areas, depressions may be filled with water during heavy rain or melting snow, predominantly in early spring.

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