A really great picture! The kid on autumn's head and the birds are really cute! Awww! :-D
I love the colour composition (/transition) of all sorts of green with all sorts of orange/ yellow/ red. The change of nature from lush green into warm colours is really quick to grasp from your picture. You can even guess autumn's fruit like grapes, apples, etc.. The falling leaves are as well in there as well! The grey background remembers of rain clouds being a part of autumn. The mischievous smirk on autumn's face remembers me a bit of the fast changing weather in this season.