In January 1922, [Millay wrote in a letter to Arthur Ficke]: "I hold a very nervous pen lately. Does your hand get that way sometimes, so that you want to dig in the earth with it, or whittle it, or thrust it into a broad fat back, – anything but write with it?" (Letters, 143). In "Sonnets from an Ungrafted Tree" it is possible to see her using her art to develop a perspective on the aggressive impulses she was feeling…

This sonnet sequence is notable in Millay for its rendering of character, its imagism (since almost everything is "told" in pictures of the body and the domestic and natural worlds), and for its restraint. We are never informed… of the reasons the woman left her husband or precisely why she returned "loving him not at all." …As readers we are the ones who see her engaging in the tasks assigned to women: setting the house to rights, making the tea and the fire, giving "of her body’s strength" to the man as though he were a child whose hands needed steadying about the cup. Furthermore, Millay invites us to see this woman’s impulses as both mediated by culture and masochistic in the sense Mary Ryan uses that term, where gratification comes from an activity which is stressful and self-defeating. Like a magazine housewife, this woman learns to

Polish the stove till you could see your face,

And after nightfall rear an aching back

In a changed kitchen, bright as a new pin,

An advertisement, far too fine to cook a supper in.

The use of "you" and "your" … seems to make this activity a ritual of capitalism, "an advertisement" of the role assigned to women who must make their kitchen "bright as a new pin" despite the fact that it then becomes unusable.

The last line of the couplet, with its extra syllables, suggests a metaphor for the disillusionment the woman feels with her life in general. In pursuing the pattern of romantic love given by patriarchy, she discovers not that her husband is a brute, but that he becomes an accomplice in continuing, rather than a partner in terminating, her frustration.

…[T]he woman now seems to feel that her body has in some way betrayed her. By flashing a mirror in her eyes at school, [her husband] appeared to give her her body in a new way. He appealed to her narcissism. But like the male gaze which promises subjectivity to the woman only to betray that promise in the end, desire for the other’s body that is actually desire for her own selfhood confuses the woman as to her real goal. The young woman cannot know herself by looking into this mirror. But she believes her needs addressed by the desire he seems to arouse in her: "And if the man were not her spirit’s mate, / Why was her body sluggish with desire?" …

Only when her husband is dead, and "From his desirous body the great heat / Was gone at last," can she begin to find her own way. At the end the poet says:

She was the one who enters, sly and proud,

To where her husband speaks before a crowd,

And sees a man she never saw before –

The man who eats his victuals at her side,

Small, and absurd, and hers: for once, not hers, unclassified.

In this way she becomes "an ungrafted tree," set free from her younger self who has been inscribed within the structure of another’s life. The poem suggests that even during their separation the woman was not wholly free, so that when she returns to "the wan dream that was her waking day," she is merely "borne along the ground / Without her own volition." Who, then, is the "strange sleeper on a malignant bed"? Is it her husband or herself, grafted onto his need for her?