ALS WALK, APRIL 20

Santa Rosa: Register for the annual Santa Rosa Walk to Defeat ALS (Lou Gehrig’s Disease) on April 29 at Howarth Park. The family event includes a 1.5-mile walk, music, food and kids’ activities. Same-day registration at 9:30 a.m. also is available. For information and registration, visit web.alsa.org/2017santarosa. All funds raised for research, services and public policy support the ALS Association Golden West Chapter.

EARTH DAY, APRIL 22

Santa Rosa: Free family-friendly Earth Day on Stage celebration at City Hall, 1st and D streets 12-4 p.m. Saturday includes live performing arts, exhibits and local beer, wine and food. Call 707-543-4222 for information.

PARKS CLEANUP, APRIL 22

Sonoma, Healdsburg: Volunteer to remove invasive plants and trash along Sonoma Creek at Maxwell Farms Regional Park, 100 Verano Ave. in Sonoma or spread mulch at Riverfront Regional Park, 7821 Eastside Road in Healdsburg 9 a.m.-12 p.m. Tools, gloves, drinks and snacks provided. Volunteers 14-17 need a parental permission slip. Call 707-565-3356 for information and RSVP.

CAMPFIRE, APRIL 22

Santa Rosa: Learn about the habits of nocturnal wildlife during a leisurely walk and make s’mores around a campfire 7-9:30 p.m. at Spring Lake Regional Park. Meet at the Group Campsite from the Newanga Avenue entrance. Bring a flashlight and water bottle. $7 parking. Call 707-565-7888 for information

OVERNIGHT BACKPACKING, APRIL 22-23 Glen Ellen, Santa Rosa: Nine-mile trek for intermediate hikers at Jack London State Historic Park and North Sonoma Mountain Regional Park and Open Space Preserve, 2 p.m. Saturday until 10 a.m. Sunday. Meet at 5297 Sonoma Mountain Road and shuttle to Jack London Park to begin the hike. $100 for adult and two children, $50 for each individual child. Parking $7. Call 707-565-2041 for information.

BLUE HERON WALK, APRIL 25

Healdsburg: Learn about the great blue heron during a 2.5-mile walk to view nesting sites along the Russian River at Riverfront Regional Park, 7821 Eastside Road, 6-8 p.m. Tuesday. Parking $7. Call 707-433-1625 for information.

-James Lanaras