At 6:30 p.m. Tuesday, December 5, soil scientist and Piedmont Master Gardener Dr. Linda Blum will present “Earthworms: Friend and Foe” at The Center at Belvedere, 540 Belvedere Blvd. in Charlottesville. To register for the free program, visit https://thecentercville.org/calendar/event/106826/3. Most gardeners view the presence of earthworms in their soil as a huge positive, but Blum will explain that earthworm activity is not all beneficial. For example, it can increase greenhouse gas emissions from soils, disrupt nutrient cycling within the soil and promote the movement of nutrient pollution from agricultural fields to adjacent waterbodies. Her talk will include many other surprising facts about the biology, geographic distribution and ecosystem impacts of native and invasive earthworms. It will also provide information on how to identify and control the spread of the most recent invader, Amynthas agrestis, the Asian jumping worm.