Got my British Driver's Licence

My British provisional driving licence came the other day. According to the codes on the licence, I can now drive agricultural tractors, "mowing machines or vehicles controlled by someone on foot", and mopeds. You need a licence to be able to mow your grass, particularly with a riding lawn mower? Why are they allowing anyone who wants a car licence to be able to drive tractors on the road? The licence itself looks like I made it in five minutes in photoshop. It doesn't even specifically say where its from. I understand that its based on the EU standard design, but you would think the country name should be somewhere. If you were to show it to someone in America, they would probably think it was a fake.