In Scout Momaday, said on page 3, "The young Plains culture of the Kiowas withered and died like grass burn in the prairie."
Similes use like and as to compare someone or something and a metaphor doesn't.
Example of a metaphor: Her hands turned to ice in the cold wind of the Autumn.
Your hands only felt like ice and didn't actually turn to ice.
The first 8 lines make the poem sound like bad news, and the word "contagious" sets the mood for the poem. The pastoral tradition celebrates the beauty of the natural world and the simple pleasure of living in the countryside. However, the first 8 lines of the poem seem to claim the exact opposite, with words like "contagious" "surge" "cold", and "waste."
