The Weight of a Tree

Early Sunday morning I went to the NE Gate of the Woods and hiked in to the big blowdown by the Wash. I cleared away tangled broken branches of elm, oak, hackberry and pecan to get to the double trunked big pecan resting across the trail. This was a mature tree with a 15 inch and 20 inch diameter trunks at 30 feet up the bole and a full crown of green leaves 30 feet further along the bole. It had blown down two years ago but maintained enough root contact to keep a green crown growing. It was suspended five feet above the trail so I had left it and just ducked under each time I passed by. Now it had fallen further to block the trail and I reluctantly decided to cut a section to restore the trail route.
The saw was reasonably sharp but it was still dicey cutting once, twice, three times, trying to get through and not knowing how the heavy tree would turn, jump, spring etc.
The weight of a full tree like this is just enormous. I paused and thought how remarkable that all the large trees around me routinely support tons of weight.. sometimes tilted, or extending away from the main trunk as large heavy branches.
As I was leaving, I noticed a large tall Albizzia mimosa, probably the parent tree of the two I had cut earlier this summer along the Creekside Trail. It was in flower and had new hanging seed pods. I cut it and will watch to see that it does not survive. Beautiful invasive tree.