Spend the money and call in a professional to get the ground cleared. A good landscaper (or similar) will have the tools needed to clear this area quickly and they will be able to offer advice on how to keep the area clear or perhaps you can pay them to come in once a month to maintain the area. Sometimes we try to take on too much ourselves, when there are people who are fitter, set up and ready to go and will take the rubbish away - hence for the big stuff, I call in the professionals.

I'd love to, but can't afford it..... :(