The Desolation of the Dragon, also known as the Desolation of Smaug, was a bleak and barren desert around Erebor and Dale, charred and blackened by the burning breath of Smaug in the days of the dragon Smaug.
The borders of the Desolation harboured some birds, but there was little grass, neither trees nor bushes, only broken and blackened stumps at its heart.
The area that later became known as the Desolation of the Dragon had been green and fair before the arrival of the dragon and probably encompassed arable lands to produce food for the city of Dale.
In T.A. 2770 the dragon Smaug attacked Erebor and destroyed the Kingdom under the Mountain and the city of Dale and probably started to create the Desolation of the Dragon by burning the landscape with his fiery breath.
After Bard killed Smaug in T.A. 2941 the desolation recovered, the town of Dale was rebuilt in T.A. 2944, the fields in the valley of the River Running were tilled again and the former desolation was filled with birds and blossoms in spring and with fruits in autumn.