Have been laid to rust upon the green

• laid on → have been laid to rust upon
  • A first-draft version of Finnegans wake

• rust: (Dutch) rest → Dutch because of the Dutch House of Orange from which the hero of the Irish Protestants, William III (King Billy, William of Orange), came

• laid to rest: dead and buried → the Orange invaders have been laid to rest

• rust: iron oxide → rust turns iron orange

• rut: sexual intercourse among mammals → in this context, laid also has sexual overtones