carse

noun1

1. •
   (Scotland) Low, fertile land; a river valley.

   • In the Carse of Gowrie to all the flat land , which is a great proportion of the district , is a deep rich clay — 1799

noun1

1. •
   An area of fertile, low-lying (typically alluvial) land occupying certain Scottish river valleys, such as that of the River Forth.