Tricky Ground - Nan C Ballard - Bog

Lee Vawn-Cory and Seth Reilly discovered a community of non-human castaways whose existence threatens the future of the human settlement on the frontier planet Carico. The leader of the hidden enclave frees Seth and Lee to go back to the human settlements with one task - deliver a message of peace to Carico's leaders. Lee and Seth have miles of wilderness to cross on horseback, pursued by a contingent from the enclave. And among their fellow humans, they don't know who to trust and who has their own plans for the planet. The future of Carico is on the line.