I was working outside today and found about 6 more.
The Maine Department of Agriculture, Conservation and Forestry says there are 4 species of lady's slippers in Maine. The most common is the pink, (sometimes white), lady's slipper, the yellow, the showy, and the ram's head lady's slipper. The yellow is rare in Maine and the ram's head is rare globally. It looks like we'll have a white.
At our old house we had some Trillium that grew very early in the season. It was sort of brick red. And behind our barn where it was damp we had a lot of jack-in-the-pulpit. All wild plants you don't see everywhere.
Thanks for the replies.