And does it matter what sort of rope I use? I saw some blue nylon rope in the local supermarket this morning. It's about half an inch thick. Is that strong enough for safety and for lowering limbs?
Sure....them tree ropes are overrated anyway. When I say overrated, what I mean is.....
My brother Daryl and I were going to play a practical joke on our other brother Daryl. He'd just come home with a Yugo that somebody sold him to scrap, and we wanted to hide it from him. So we tied one of them fancy 100' tree ropes to the bumper, and the other end to a tree by the cliff behind the house. Daryl put the yugo in neutral, and we started it rollin towards the cliff.
Well, it occured to me that we might need to bring the car back up sometime, so I ran around and pulled the E-brake, then smacked Daryl upside the head. "How we gettin this thing back up?" I said. Well, he smacked me upside my head, and said, "Duh, don't worry about it.....my buddy down the road has one of them GCRS's" "What's a GCRS"? I asked. Then he smacked me again. "It's a Good Car Raising System", he said, "No worries."
So we took off the E-brake, and pushed it over. Now, that rope said it would hold over 6000 pounds, and that Yugo only weighed like 1650 pounds. The guys that made that rope must have made a mistake or lied, because when the Yugo hit the end of the rope, it snapped with the loudest "CRACK" I've ever heard.
Daryl was inside the house, and heard the "CRACK", and came runnin out screamin and yelling. He thought we'd snuck into his stash of M-80's again, and he was pissed.
My other brother Daryl calmed him down by telling him we hadn't touched his M-80's, that we were only doing some break strength testing on some ropes. It was morning before Daryl realized what we'd used as weight to test the ropes, but by then my other brother Daryl and I had already drained the (thankfully intact) oil pan from the Yugo, and were off to sell a batch of two cycle oil.
So to sum up, don't waste money on expensive ropes, you can get more and safer use from braided twine you can get for free from local farmers. Just be careful about using strands which were left laying on the wet ground for a year or so.....but that's another story.