Cut pine needles into small pieces and place them in a medium bowl.
Cover with non-chlorinated water and sweetener.
Cover with a cloth, place in a warm environment (70-80 F), and stir twice daily for 60 seconds until bubbly (3-7 days).
Strain the liquid into another bowl and add sugar and acidity to taste.
Pour into a plastic or glass flip-top bottle.
Let sit for 4-48 hours at room temperature until ideal carbonation is reached.
Refrigerate, enjoy over ice, or in a cocktail with gin.
