Big Bog State Recreation Area: Master naturalists will post themselves along the boardwalk from 9 a.m. to noon to answer questions and help visitors find plants, birds and unusual features. Musician and storyteller David Leonhardt will tell tales about early life in the Big Bog and play the carpenter saw from 7 to 8 p.m. near a campfire on the Red Lake beach. More information: 1-218-647-8592, mndnr.gov.

Lake Bemidji State Park: Naturalist and photographer Sparky Stensaas will present a program at 8 p.m. on "Owls to Orchids: Magic and Mystery in Our Northern Bogs." A naturalist also will be stationed along the boardwalk from 11:30 a.m. to 1:30 p.m. Sunday, July 27. More information: 1-218-647-8592, mndnr.gov.