TCI recommends several tools. The best piece of gear is a throwing bag. Lines of 150 feet are best. A skilled climber can lob such a line over a branch 70 feet high. A weight of 16 ounces or less is used.
Some professional climbers use a throwing pear but that is a bit outdated.
Throwing pears are lead weights encased in foam rubber. They tend to bounce off the branches more than the bean-bag weights. Extra tall trees call for different tools. Some trees grow so tall that 70 feet won't get you half way to the first branch. Slingshots are sometimes used with fishing reels.