Heartwood by Amity Gaige

When Valerie Gillis disappears while hiking the Appalachian Trail, Maine game warden Beverly Miller is put in charge of the case. Valerie failed to show up to meet her husband, Gregory, who was supporting Valerie throughout her journey by bringing her food and gear. Valerie was last seen two days before by some fellow hikers. Heartwood explores three women's stories--Valerie's while she's missing on the trail, Bev's as she leads the investigation, and that of Lena, who lives in a retirement community in Connecticut and spends her days birdwatching and foraging the surrounding land. A leisurely-paced novel exploring the women's lives and how they intersect.