This is a relatively simplistic collage.

Photo #1 shows the goldenrod gall fly (Eurosta solidagensis), the insect responsible for the familiar round galls on goldenrod stems.

Photo #2 shows the formed gall in winter.

Photo #3 illustrates the fate of many galls, as chickadees, woodpeckers, squirrels and possibly other creatures, find the larva a good treat; here you can see the galls have been opened by a woodpecker or a chickadee.

Photo #4 is an opened gall showing the fly cocoon.

Photo #5 is the cocoon.

Photo #6 is the half-formed goldenrod gall fly.