Autumn leaves...

Most years, the autumn leaves are long gone by the end of September. This year, while some of the trees have shed their leaves, others are still green or are in some shade of yellow/orange in early October.

It's hard to tell if this is really unusual (a sure sign of global warming?) or I'm just noticing something that doesn't mean much (like always). While they do keep records on when the leaves first appear in the spring; it's referred to as green-up and usually occurs in mid-May when the hills around town turn green, there's no record for fall.

I think they should note the date when the leaves finally lose their color and are mostly gone. Call it brown-down, the day in autumn when enough leaves have fallen that the hills turn brown.