Volunteer for roadside litter cleanup or help remove buffelgrass; learn about desert trees and their care; recycle cell phones, ink cartridges, plastic bottles, empty plastic plant containers and aluminum beverage cans, and win raffle prizes at this event organized by Tucson Clean and Beautiful from 8:30 a.m. to 12:30 p.m., Sunday, April 3. Call 791-3109 for more information.