Many of the Woodmen's crates and containers were damaged during the avanc-attack. They managed to salvage many of the contents, but the containers need to be patched.
'${PLAYER}, will you hear me out? When the demons of the Rushgore attacked our boats, many of our crates and containers were damaged. We salvaged most of the contents, but the containers need to be patched to transport them safely when we arrive in the land of the Horse-lords.
'Will you go forth into the marsh and collect reeds strong enough to bind the containers and mud to patch them? While we scouted for an ideal camp-site, I saw a great burrow of mud and clay to the north-east of here. Perhaps you may find the materials I require there?
'Thank you for any assistance that you will provide.'
The burrow Gisalic mentioned lies to the north-east of the Woodman camp in the Rushgore.
Gisalic asked you to collect reeds and clay from the burrow he saw nearby.
Gisalic is at the Woodman camp at the heart of the Rushgore.
You should return the materials you gathered to Gisalic and tell him of the insect infestation.