Hello Trudy: you are witnessing the male and female flowers being expressed on an evergreen. The male flower is normally in the upper portion of the evergreen and once the male flower (a catkin looking structure) opens the pollen uses gravity to pollinate the female flowers below. If you look closely at the evergreen when the pollen is there, look for small green cones, the female flower. The picture of the spiky structures are the previous year cones that have opened up to allow the arborvitae seed to escape.
