Last week was peak fall color in many areas of central and southern Minnesota.  This year’s color has been much more vibrant – perhaps due to our copious amounts of rain in June, the lack of extreme heat in the summer months, and the delay of a killing frost.  I spent the morning at William O’Brien State Park, nestled beside the St. Croix River.  The park has a riverside trail that meanders alongside the St. Croix, and it also has an “upper” section with a prairie, an oak savanna, meadows and forests.  This area was brilliant in color; the treeline was ablaze and the prairie grasses were golden.  The sure signs of fall were the empty bluebird houses.  These will remain vacant now throughout the winter with its snow yet to come, until we pass into spring and its burst of green.