The Louisiana and Texas gulf coastal prairies are the southern most extension of the vast tall grass prairies that once graced the midsection of the United States. The Louisiana Coastal Prairie, known as the Cajun Prairie, was once a network of botanically rich grasslands that covered over two million acres in the southwestern part of the state. Today, due to rice farming and development, it has dwindled to less than fifty acres and is considered one of Louisiana's most threatened ecosystems. There are other prairies in Louisiana known as Inland Prairies. They are usually less than twenty acres or less in size and distributed in small scattered systems. The soils of the inland prairies are strikingly different than those of the Cajun Prairie. Cajun Prairies were generally flatlands while the Inland Prairies are found as islands of grassland surrounded by forests. These inland prairie soils are usually associated with ancient marine deposits. The suppression of trees in the Cajun Prairie is attributed to a hard clay layer under the topsoil. In the inland prairies, tree suppression is a result of low oxygen levels in the soil due to heavy clay consistancy.
In the map above, the remaining prairie remnants are shown in red. These remnants have increasingly been reduced by the lack of presence of fire and by further development. Some are privately owned
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