Answer:
As soft as silk, as white as milk, as bitter as gall, a thick green wall, and a green coat covers me all.
My life can be measured in hours. I serve by being devoured. Thin, I am quick. Fat, I am slow. Wind is my foe.
There are 30 cows and 28 chickens. How many didn't?
I bind it and it walks. I loose it and it stops.
What makes a loud noise when changing its jacket, becomes larger but weighs less?
In all the world, none can compare, I am a tiny weaver; my deadly cloth so silky and fair. What am I?