My trees where cut down without my authorization. What do I do?

I was contemplating cutting down three holly trees growing too close to my house. One tree company asked me to sign the quote so that they could prove to their boss that they where working - that we actually met and that I recieved a price. The paper I signed says "proposal" right on the front, it does NOT say contract. I just wanted quotes. Well, now my trees are gone, and that company cut them down by mistake. I never gave permission or authorization. What do I do?