48 



widths of 500 feet or more for suitable crane roost sites 

 during migration. Acquisition and conservation ease- 

 ments are useful tools. 



Forested Wetlands of the Lower 

 Mississippi Alluvial Plain 



The bottomland hardwood forests of the lower Missis- 

 sippi floodplain are among the Nation's most important 

 wetlands. They are prime overwintering grounds for 

 many North American waterfowl, including 2.5 million 

 of the 3 million mallards of the Mississippi Fly way. near- 

 ly all of the 4 million wood ducks and many other migra- 

 tory birds. Numerous finfishes depend on the flooded 

 hardwoods for spawning and nursery grounds. These 

 wetlands also support many other wildlife, including 

 deer, squirrel, raccoon, mink, beaver, fox and rabbit. 

 They also play a vital role in reducing flooding problems 

 by temporarily storing large quantities of water and by 

 slowing the speed of flooding waters. In the process, 

 these wetlands remove chemicals from the water such as 

 fertilizers and pesticides and trap soil eroding from near- 

 by farmlands. 



Onginally, the Mississippi Alluvial Plain included 

 nearly 24 million acres of bottomland forested wetlands. 

 By 1937, only 11.8 million acres or 50^7^ of these re- 

 mained. Today, there are less than 5.2 million acres left, 

 roughly 20% of the original acreage (Figure 44; MacDon- 



c 



O u. 

 W Q 



o< 

 <nX 



^ -I 



6- - 



■r 



I I 



1937 1947 1957 1967 1977 1985 1990 1995 



YEARS 



Fig. 44. Actual and projected losses in bottomland forested wetlands 

 of the lower Mississippi Alluvial Plain (from MacDonald, et al. 1979). 



aid, et al. 1979). Over half of this wetland is in Louisiana, 

 with large amounts also in Arkansas and Mississippi. 

 These forested wetlands have been cleared and drained 

 for crop production (Figure 45). Federal flood control 

 projects and small watershed projects have accelerated 

 wetland conversion to cropland, especially from the 

 1950"s to the present. An estimated 2% of the remaining 

 bottomland forests are lost annually. 



Historically, cotton and com were the primary crops 

 raised on former bottomlands, but since the mid-1950's, 

 soybeans have dominated. In 1977, cropland acreage in 

 soybeans amounted to more than the combined acreage of 

 the four other principal crops - cotton, wheat, rice and 

 com. Soybeans have major advantages over the other 

 crops: ( I ) they have a very short growing season, so they 

 can be planted in areas that are flooded till late June, and 

 (2) they can be planted in a variety of soil conditions. 

 Other crops, like cotton, require better drained soils than 

 soybeans or rice. Heavy foreign demand for soybeans has 

 made it the most lucrative cash crop. Traditionally, natu- 

 ral stands of bottomland hardwood forests were cut for 

 timber. Recently, in an effort to maximize timber produc- 

 tion, Cottonwood and other silviculture plantations have 

 been established to a limited extent. However, the eco- 

 nomics of hardwood production cannot compete with 

 farm crops, where they can be grown. The net economic 

 return per acre is twice as high for familand as for forest. 

 Thus, conversion of bottomland hardwoods to cropland 

 can be expected to continue in the Mississippi Alluvial 

 Plain as well as elsewhere in the Southeast. These losses 

 seriously threaten some wildlife populations and increase 

 the frequency of damaging floods like the April 1983 

 floods that caused millions of dollars of damage in Lou- 

 isiana and Arkansas. 



The Federal Clean Water Act can be instramental in 

 regulating conversion of bottomland hardwood forests to 

 agricultural uses. A 1979 U.S. District Court decision 

 (Avoyelles Sportsmen's League v. Alexander) stated that 

 a Section 404 permit is required for land clearing of 

 wetlands for agriculture. Subsequently, the Corps of En- 

 gineers took a conservative position and regulated land 

 clearing only in the Westem District of Louisiana. On 

 September 26, 1983, the Fifth Circuit Court of Appeals 

 decision (Avoyelles Sportsmen's League v. Marsh) af- 

 firmed the district court's opinion by rejecting the conten- 

 tion that land clearing is a nomial famiing activity exempt 

 from Section 404 pemiit requirements. This decision pro- 

 vides the legal framework for protecting remaining bot- 

 tomland wetlands as well as other inland wetlands subject 

 to agricultural conversion. In early 1984, an out-of-court 

 settlement agreement on a U.S. District Court case (Na- 

 tional WildliTe Federation v. Marsh), among other things 

 ordered the Corps of Engineers to issue a regulatory guid- 

 ance letter regarding the Avoyelles Sportsmen's League 

 decisions. The future outcome of these decisions should 

 lead to improved wetland protection under the Clean Wa- 

 ter Act. 



