|I'm looking for something that grows fairly fast, zone 5, and will work as a wind/privacy barrier and grows in rocky soil.|
|You'll have more success with native plants than cultured exotics in your gardening region, so you might want to consider Curlleaf Mountain Mahogany (Cercocarpus ledifolius). An adaptable shrub to small tree with 1 to several trunks, it grows on average to 15 feet tall, but can reach up to 35 feet tall. It flowers May to July and reproduces from seeds. Hope this works for you!