With Isabel bearing down on the US east coast I spent most of daylight hours today cutting branches from a couple big trees in the front yard. (I live in the Washington DC area.) A new gas main was installed a couple months ago and they cut about 40% of the roots of one of them looking for the pipe. :-( A good hurricane blow may bring it over, but maybe I got rid of enough wind resistance.
The largest branch I cut was 10" to 11" in diameter at the trunk and it came within inches of taking off the rain gutter as it descended. Better to take it down now than have it go through the roof if the tree gets blown over. It took a long time to cut with my manually-activated pruning saw. Standing on a wobbly ladder and hanging onto a limb with one hand left me one hand short of using any power tools. ;-)
-- Mark