These petite, gorgeously understated wetland plants are called pipeworts (Eriocaulon aquaticum). Another common name is seven angled pipewort - their flower stems have seven ridges that twist along and around the stem, some of which are visible in this next photo.
Many aquatic plants are water- or wind-pollinated, but these little cuties need insects for pollination. They are really tiny, as I hope this last photo illustrates
It's uplifting to see 'fields' of them like this
