The range of the green-striped darner over laps with the range of the Canada darner, which is found mostly in the northwest portion of North America, in the middle of the continent. Because of that we see both species here. This can be difficult since both of these two species look very similar. The best way to identify which species that you have, when not under a microscope, is to look at the notch on the front side stripe of the thorax. If the notch is shallow, as you can see in the top picture, then it is probably a green-striped. If the notch is deep then it is probably a Canada darner.
Like all darners the green-striped darner is a strong flier, often catching and eating its prey i flight. This makes it difficult to photograph darners. Fortunately they seen to land much more often in the fall. Usually when they land they have something to eat. These pictures where taken by the Old Cedar Avenue Bridge in the Minnesota Valley NWR at the beginning of October.