 Second units also shot the Ford of Bruinen chase and the deforestation of Isengard.Liv Tyler generally came to New Zealand for stunts, and spent five days on a barrel for Bruinen while riding double Jane Abbott got to ride on horseback.During the first month of filming, Stuart Townsend was deemed too young to play Aragorn, and within three days Viggo Mortensen became his replacement, just in time to film the Weathertop sequence.