Join the Ecological Landscaping Association on Tuesday, June 12, from 10 – noon, for a professionally guided tour to learn the background of this bio-filtration system installed by New England Environmental that captures and filters stormwater before it enters Willow Pond.  There has been an installation of more than 2,000 individual plants of aquatic-emergent species.  $20 ELA members, $25 non-members.  Register on line at https://www.eventville.com/catalog/eventregistration1.asp?eventid=1009406, or email Penny at ela.info@comcast.net.  Meet at Mount Auburn Cemetery, 580 Mount Auburn Street in Cambridge.