Now wait a minute.... My wife moved here from southern Cali 30 years ago, and she claimed the grass turned brown and quit growing.
Matter-of-fact, my impressions from listening to her talk leads me to believe that's how they determined the passing of the seasons.
Sparse, green grass with bare spots in the lawn = Spring.
Full coverage of brown grass = mid to late summer.
Sparse, brown grass with bare spots in the lawn = Fall.
Mostly brown grass, bare spots, some new life (green) starting to appear = winter.