University of Maine Cooperative Extension will offer several educational talks and demonstrations Aug. 5–8 at the Northern Maine Fair Exhibition Hall, 84 Mechanic St., Presque Isle.    “Extension Talks” begins at 6 p.m. Aug. 5 with an overview of soil health, followed by dessert-making with an electric pressure cooker at 7 p.m. Other topics include growing read more UMaine Extension offers talks at Northern Maine Fair Aug. 5–8