Depending on where you live, your pine cones might have bugs in them if you collected them from outside.
You have 2 options for getting rid of them.
- Place the pine cones in a bag, squeeze out most of the air, seal it, and leave it for a week.
- Place the pine cones on a foil lined baking sheet. Preheat your oven to 250 degrees, and bake for 25 minutes.