'In the past, the Orcs that have attacked have been of the Tarkrîp tribe. The bloodlust of that tribe usually cause them to throw themselves heedlessly into the battle, without forethought.
'The Orcs that now move on Trestlebridge appear to be of the more powerful Ongbúrz tribe. These warriors are stronger and more skilled. The townsfolk will not be able to stop them. I would send a party of my men to aid them, but all my kin are dealing with matters in the east.
'You and I may reach them in time, however. You have done much already, but I would ask for your help in this battle. Gather what warriors you can and return to me. But make haste...Trestlebridge does not have much time.'
Upon returning from Trestlebridge with Nellie Boskin's refusal to join the Council, Halbarad informed you that a large force of Orcs was moving on Trestlebridge.
Travel with Halbarad to Trestlebridge and aid in its defence.
Halbarad told you that the Orcs moving on Trestlebridge are from the more powerful Onburz tribe. The townsfolk will not be able to defend against them alone. Halbarad instructed you to gather allies and return to him.
Nellie Boskins can be found in Trestlebridge.
At Halbarad's side, you helped defend Trestlebridge from the Orcs that sought to destroy it. At the conclusion of the battle, Nellie Boskins asked to speak with you.