This miscellaneous quest is activated upon reading Ysolda's Message found on Ulag's corpse in Sleeping Tree Cave. The message details an agreement Ysolda had with Ulag to deliver Sleeping Tree Sap to her stall in Whiterun.
Upon entering Sleeping Tree Cave the body of Ulag can be found nearby the giant that presumably killed him. Ysolda's Message will prompt the Dragonborn to speak to Ysolda about Sleeping Tree Sap.
Ysolda will explain that Ulag was her supplier, but given his death she has no way to retrieve any more Sleeping Tree Sap. She will however offer to buy any that the Dragonborn may retrieve or find.
The quest is then considered complete.
|Ysolda's Shipment – dunSleepingTreeCampQST|
Note: This quest is never actually shown completed in the journal stages.