As requested by Espen204 here's an updated map with Oleander Sage locations if you guys/gals would like any other additions please feel free to send me a message. Happy trails y'all! :
Plants - Red Dead Redemption 2 Walkthrough & Guide - GameFAQs
Red Dead Redemption 2 ONLINE - OLEANDER SAGE LOCATIONS - YouTube
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Red Dead Redemption 2 Oleander - Where to Find - GameRevolution
Sage location in Red Dead Redemption 2 | Shacknews
RDR 2 | Location of the Oleander Plant / Oleander Sage | Red Dead Redemption 2 - YouTube
Red Dead Redemption 2 Where to find Oleander Sage
Sage location in Red Dead Redemption 2 | Shacknews
Red Dead Redemption 2 Plants Locations
Red Dead Redemption 2": Herbalist Challenges - LevelSkip
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