Answer:
The root tops the trunk on this backward thing, that grows in the winter and dies in the spring.
I run through hills. I veer around mountains. I leap over rivers. And crawl through the forests. Step out your door to find me.
Reaching stiffly for the sky, I bare my fingers when its cold. In warmth I wear an emerald glove and in between I dress in gold.
The more holes you cover the lower it goes.
All about, but cannot be seen, Can be captured, cannot be held, No throat, but can be heard.
People take me on walks and I run and have fun. What am I?