What is the incident of poem farewell to barn stack and tree?

The poem "Farewell to Barn and Stack and Tree" by Alfred Lord Tennyson describes the poet's feelings of nostalgia and sadness as he bids farewell to the natural world around him. The incident in the poem is the speaker's departure or separation from the barn, stack, and tree that hold significant memories and emotions for him. It reflects themes of loss, impermanence, and the passage of time.