I might quibble, and say that's NOT spring light. The trees are spring green, but the grass is high-grown and brown. And early morning light is softer. Hopper uses that hard-edged, cold light in (almost) all his pictures, but here's one that disproves the general rule:
That seems to me to be a more realistic grasp of light. As I said before, I think his usual lighting is symbolic or at least intended to set a mood.
Now that one (the bridge) really is downright depressing! Not my cup of tea, at all.
I interpreted the Cape Cod painting as late summer ... grass turning brown, while the trees are still green. Or perhaps that's just my warped Californian view, since un-irrigated fields are indeed pretty brown this time of year ;-)
Anyway, I'm off to work ... nice chatting with you :)