Just finished up this years scarecrow, so I thought I'd give you a look.
Glued up and formed a styrofoam head, sized to fit the hat, and draped/formed damp burlap over it. After it dried I gave it a good coat of spar varnish which hardened it up. Sticks to fill out the body and a trenchcoat to finish. Not sure how it will hold up as I've never tried it before. Very quick to make. I will add some cornstalks, but haven't picked them up yet.
Not great pics, the lighting was bad and so is my photo skill