Why is the Shami tree worshipped on Vijayadashami?

The Shami tree is worshipped on Vijayadashami as a symbol of victory, protection and successful completion of difficult tasks. According to Mahabharata, Pandavas hid their weapons in a Shami tree during final year of their exile, when they lived in disguise. Arjuna later recovered the weapons to get ready for battle, making the tree symbol of preparedness and triumph.