"Sumer is icumen in/ Lhude sing cuckoo" begins a very old English poem in praise of that season. Pound's verse is a take on it which reflects the feelings of many people about winter at the moment. It is of course a literary joke, but then he was a very literary young man when he wrote it. When he got more serious, practical and down-to-earth in his work and precepts, he succeeded in changing the diction, subject matter, and direction of English poetry, making it less "poetic" and capable of reflecting the real emotions of people in the modern age.
Winter is icumen in,
Lhude sing Goddamm,
Raineth drop and staineth slop,
And how the wind doth ramm!
Skiddeth bus and sloppeth us,
An ague hath my ham.
Freezeth river, turneth liver,
Damn you, sing: Goddamm.
Goddamm, Goddamm, 'tis why I am, Goddamm,
So 'gainst the winter's balm.
Sing goddamm, damm, sing Goddamm,
Sing goddamm, sing goddamm, DAMM.