Personification is giving human qualities to inanimate objects or plants and other animals. In the first stanza, the tree wears the scarf. The scarf is the vine that is growing up the tree like a python in the tree’s old age. The song “sung darkling from our tree” might be the wind rustling through the branches and/or the leaves. Trees don’t ‘sing.’ This is personification. Other examples of the personification of the tree are ‘the tree’s lament’ and its ‘eerie speech,’ which could just be the speaker’s manifestation of the tree’s pining it its old age or it could be the wind in the leaves or the creaking of an old branch.
Another example is the waves kissing the shore. Dutt personifies the tree because it represents the nostalgic link to her past and by willing the immortality of the tree in the last stanza, she is also willing the immortality of her memories, which includes she and presumably her departed loved ones.