Book 2. The Two Towers. As Aragorn searches for Frodo, he suddenly hears Boromir's horn. He finds Boromir mortally wounded by arrows, his assailants gone. Before Boromir dies, Aragorn also finds out that Merry and Pippin were kidnapped by Saruman´s Uruk-hai in spite of his efforts to defend them, and that Frodo had vanished after Boromir had tried to take the Ring from him and that he truly regretted his actions. In his last moments, he charges Aragorn to defend Minas Tirith from Sauron. With Legolas and Gimli, who had been fighting Orcs themselves, Aragorn pays his last respects to Boromir and sends him down the Great River Anduin on a funeral boat, the usual methods of burial being impracticable. Aragorn, Legolas, and Gimli then resolve to follow the Uruk-hai captors. Meanwhile, after some hardship, Merry and Pippin escape when the Uruk-hai are attacked by the horsemen of Rohan, called the Rohirrim or "Riders of Rohan". Merry and Pippin escape into the nearby Fangorn Forest, where they encounter the giant treelike Ents. The Ents resemble actual trees, except they are able to see, talk, and move. These guardians of the forest generally keep to themselves, but after a long contemplation on whether or not the Hobbits were friends, or foes, their leader Treebeard persuades the Ent council to oppose the menace posed to the forest by the wizard Saruman, as suggested by Merry and Pippin, as Treebeard realizes that Saruman's minions have been cutting down large numbers of their trees to fuel the furnaces needed for Saruman's arming of his dark army.