Spend a day giving back to the environment by learning easy ways to preserve parks, trails and recreation sites while stopping the spread of land-based invasive diseases. Participants take home a free boot brush (while supplies last) as well as invasive species information to help with future identification and removal of invasives. The afternoon concludes with a guided tour to learn wildlife identification techniques as well as a scavenger hunt. All ages; children under 18 must be accompanied by an adult. 11 a.m.–3 p.m. Eastman Nature Center, 13351 Elm Creek Road; 763.694.6700; threeriversparks.org.