Why Mow? It's Wild!

Areas of my "lawn" have yet to be mowed since last year. Although they look a bit like hay, I think the birds may like the grass going to seed for them.
Extra: a volunteer milkweed plant has threaded its way though the boardwalk boards. Not sure if it will produce any flowers.
The temperature has taken a nose dive to nearly morning frost again! It was 88º two days ago. This morning I considered turning on the heat because it was 38ºF outdoors.
Two days of summer and that's it for now! I would like a steady 72.