The day was cloudy and cool. Recent rains created some muddy and water logged spots. The leaves were out, so we practiced birding by ear. Only occasionally did we get to see the birds. Seven of us gathered for the Greenstone trip.The roadside started us off with a variety of birds. A Green Heron flew over. Several Yellow Warblers were calling. One Blue-gray Gnatcatcher was sighted. Fully a third of our count was seen before starting down the trail.In the shrubby field we found a scattering of Blue-winged Warblers. This is one of their favored habitats, and one we are trying to maintain. Single Common Yellowthroats and Rose-breasted Grosbeaks were heard.In the marsh we heard an Adler or Willow Flycatcher. Not sure which. Back out at the road we got a pair of Wood Ducks flying over. We got some looks at an American Redstart in a tree, and a small flock of Cedar Waxwings. We had a total of 34 species, including 4 warblers.