Hi. Sure!
Spruce gum was the original chewing gum, long before anyone had even heard of chewing gum.
http://en.wikipedia.org/wiki/Spruce_gum
Sadly it went out of fashion after the sweeter varieties came on the market.
I learned how to do this from my granddad.
The key to success is to find rosin deposits that are just at the right stage of drying. Look for opaque or semi-transparent rosin of a light yellow colour. It's often deposited in wounds, or on the bark as ready-to-pick nodules.
If the rosin is too hard and glass-like inside, it will just crumble to mush in your mouth.
If it's too soft or runny, you'll spend the next to days picking spruce glue out of your teeth.
When you've found the right stuff, you have to process it a bit.
1. Remove any fragments of bark.
2. Put it under your tongue for a minute or two to warm it up.
3. Chew vigorously for a minute or so. First everything will apart, but then it starts clumping together to a ball again.
4. Spit.
5. Spit again.
6. Ideally you should now have a nice piece of gum between your teeth. The taste makes you feel like ole-time lumberjack.
