Help the Boston Natural Areas Network construct a brand new composting system and learn the science and process of composting, on Saturday, August 30, from 10 – 12 at the Norton Stonehurst Community Garden, located on Norton and Stonehurst Streets in Dorchester.  Leave knowing how to build and maintain a healthy, balanced compost pile.  Registration required by contacting 617-542-7696 or by emailing info@bostonnatural.org. Photo from www.squawkfox.com.