We studied a population of wood turtles (Glyptemys insculpta) along 42 km of a river in a national forest in northern Michigan. For each of 3 summers (1998-2000), 9 or 10 turtles were radiotelemetered and relocated 3-6 times per week; during one winter (2000-2001) 5 turtles were radiotelemetered and relocated once per month. Mean summer home range estimates using 95% adaptive kernel were 40.6 ha (range 0.4-354 ha); using the minimum convex polygon method, summer home ranges averaged 30.2 ha (range 0.2-390 ha). No statistical relationships were found between size of summer home ranges and turtle age, size, or sex. Summer home ranges in 2000 were significantly larger than those in previous years. Because 2 of the study years were unusually dry, we calculated drought indices for each year of the study. We report larger summer home ranges for wood turtles than have been reported in previous studies, including those that report annual home ranges, which may indicate poorer habitat quality in our study area or drought effects.