'its head trembles and nods' - the personification continues, as the tree now has a head. As the tree becomes human, we get the violent image of a person being hacked to death. This brings us closer to the horror of what is happening no just to Troy, the city, but to individual Trojans. The image of a tree reacting to a violent onslaught is used again in bk 4, when Aeneas the oak is battered by the pleas for him to stay in Carthage