For here were no long, straight furrows, such as could be seen in the yellow clay fields of the flat middle Georgia country or in the lush black earth of the coastal plantations.
Because the middle section of the river flows through the Loess Plateau of China, it carries a large amount of sediment, making it the most sediment-laden river in the world.
The upper part of the 'pipe', where it had been most exposed to weathering, was soft and crumbly, and was known as 'yellow ground', and it could be easily excavated by hand.
Not only had the market been flooded, but also the soft 'yellow ground' had been mostly exhausted, giving way to harder 'blue ground' which had to be broken with machinery or dynamite.