Humans are but guests on this Earth, which will surely outlive us. It did OK alone for the first few billion years, didn’t it? While we’re here, though, we should be nice to our temporary habitat. To celebrate Earth Day, which is actually April 22, Louisville Parks and Recreation is looking for volunteers to plant 100 trees in the Shelby Park neighborhood. You must sign up online beforehand. Volunteers are needed for various tasks and times throughout the day, from 8 a.m. to 1 p.m.. While ensuring the environmental health of our city, we should take care of our own, too, so masks, temperature checks and social distancing will all be required. ­