Acacia

Acacia in Freemasonry is is a symbol of the immortality of the soul. 

Acacia was used in the constructing of the sacred furniture in King Solomon's Temple.

Acacia is referred to in the Holy Bible as Shittim Wood.

This information came from my father's Masonic Bible that was given to him when he joined Kedron Lodge No. 389.

Acacia is thought of as being an evergreen tree of some type. Perhaps pine. 

Also see Sprig of Acacia.