Can I use all kind of fruit peels and pine needles in my compostor?
Multnomah County Oregon composting
Thanks for your question about composting materials. The answer is a qualified "yes." If you're referring to a composting unit like the black 'bomb' that Metro (and other outlets) sells, one of the three-bin wooden units, or just a pile that you occasionally water and turn over, the only things you want to avoid are foodstuffs that attract rodents and flies. If you're referring to a contained worm (red wrigglers, aka eisenia foetida) composting unit, you'll want to avoid citrus peels and needles--pine and fir--because they are too acid for the worms' 'taste.'
Here's a link to a Metro, a short summary about gardening with compost from the Clackamas County Master Gardeners, and, in case you're interested, another short article/video on worm composting (vermicomposting) from Metro.
Hope this is helpful. Good luck!