One way to look at this is that if it were too easy to remove trees you might take more than you really need.

For those obviously evil trees that deserve to be destroyed, a dozer driver I know puts his blade up nearly as high as it will go and either drives forward and or lowers the blade against the tree and they pretty much fall over. The root ball tends to roll out so the dirt can be smoothed over the hole left behind. Doing this while the ground is moist, but not wet, may help. It's usually a matter of long term planning and knowing which details to sweat.

A couple of years back I attended a seminar on rain water management and trees were considered pumps. The plan was to grade the landscape and collect roof water, then run the rain into troughs around the trees. The water could be held for years deep underground until the tree pulls it up to make something useful for the tree and humans, such as shade for crops, wind breaks, leaf litter for compost, fruit to eat, and for evil trees, wood to build with or burn.

Here in California, trees and water are in very short supply, so we tend to take these issues pretty seriously. I was on a jury that awarded close to a million dollars for the mistaken cutting of 60 or 70 oak trees of all sizes ($13,000 each).

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Kirk Wallace
http://www.wallacecompany.com/machine_shop/
http://www.wallacecompany.com/E45/index.html
California, USA

You should regard yourself lucky, that you may have access to that many trees. Lumber is a very valuable resource with lots of uses.

Factor in the forest in your permaculture and sustainability plans and regard it as a resource for building material and energy. Go step by step and clear as little area as possible from the trees. Calculate the size of your planned community and how much lumber and wood you might need for building purposes, and for energy provision. Take into account, that good lumber needs 50 to 100 years to regrow. Calculate how many trees you will need over that time period, and make sure, that the regrowth rate meets the the rate you take wood out of it.

When you are cutting trees, do it with the mindset of using the trees later, not with just freeing space. This leads to an approach to tree cutting with a more a quality than quantitiy focused mindset.

You do not need heavy machines for this. You can do it with manual labor, it will only need more time, but it will make what you get so much more valuable to you. You can rely on axes and handsaws, like people did very successfully for thousands of years, but you can of course burn mineral oil, contribute to planet pollution and use chainsaws, if time is pressuring you. When what you are doing is just clearing a hillside, you do need to invest in machinery anyways. A much more cost efficient approach would be to sell the wood and let the purchaser clear the hill for you, taking the wood as payment.