University of Throw Line

This article was adapted from the video of Jake Carufel demonstrating throw-line tips during TCI EXPO ’21 in Indianapolis, Indiana, last November.

Regarding throw-line tips and tricks, the first big “Ah-ha!” is to keep everything very organized. Being organized and systematic in your approach to using a throw line will keep tangles, and your frustration, to a minimum. You want a system that makes it quick and easy to make repeated throws into a tree because, let’s face it, it’s pretty rare to hit your exact tie-in point the first time, every time. So a tangle-free line in a clean storage container will assure you can make those repeated throws in the shortest amount of time.

Line storage

One of the earlier methods of throw-line “organization” was to wind it around a stick. (Photo 1) It was probably one step up from just having it in a big pile on the ground. A climber would unwind about 40 feet, or whatever the height of the branch they were trying to hit was, then throw whatever weight they were using into the tree. If the weight actually went as far as they intended, the remaining length on the stick would spin and drag, and generally create a tangled disaster. Someone finally had a lightbulb moment and created folding cubes for storing throw line, which is a common method used today.

Photo 1: Old-school stick wrapping. All photos courtesy of TCIA.

Throw cubes are like origami. They unfold to open, then fold to close into a compact triangle while keeping the throw-line contents neat and secure. But the first time you use a throw cube, it’s like a Pandora’s box. If you yank on it to try and open it, it will just spin around on the ground. Closing it without following instructions is even worse – which corner do you grab and which way is the fold? There are many ways to fold it wrong, which just adds to the time it takes to deploy next time.

Hint: There is usually an arrow visible on the top of the cube that shows which way to turn it to open and close it. (Photo 2)

Photo 2: There are directional arrows showing how to open and close the cube.

But once you get familiar with this device, it is well worth the short learning curve to keep your lines organized.

Attaching the line to the bag

It’s not just the throw line itself that is in the spotlight, it’s also the weighted bag, which is what drags the line into the tree when thrown. You need a reliable way to tie the weight onto the line, and then be able to easily untie it as well. There are many ways to attach the throw bag to the line. An example is a slippery-8 knot, which is easy to tie and untie. Thread the line through the ring on the throw bag, put a twist in the line, then thread a bight of it back through the loop created by the twist, right above the ring of the throw bag. (Photo 3)

Photo 3: A slippery-8 knot tied loosely for clarity.

Other knots that have been used are a slippery clove hitch, girth hitch and half hitches – there are plenty of ways to tie these on.

Hint: Use a knot that is easy to untie, since you will need to take the weight off frequently.


When it comes to actually throwing the throw line, there are a few different ways to try to get it into the tree. Here are two.

One-handed to the side: Take a bight of the throw line and pass it through the ring of the weight, creating a large loop. Slide the loop over your finger and let the weight hang to your side. Get it swinging and release when you have enough momentum. (Photo 4)

Photo 4: One-handed side throw.

Underhand, granny shot or cradle throw: Take a bight of throw line and loop it through the weight ring, as with the side throw. Grab the loop in both hands and center the weight between your legs. Swing it back and forth to get momentum, then release it up into the canopy. (Photo 5)

Photo 5: The underhand or cradle throw.

Throwing with any kind of accuracy requires a bit of skill, a bit of luck and lots of practice. Get a throwing method in place that you can replicate each time, and you will become more accurate sooner.

Here’s another throwing tip: You’ve got the weight swinging at the end of the line, and you’re looking at the branch you want to throw the line over. Keep your body still so the line pendulums in a straight arc. Keep your feet in the same position every time you throw.

Hint: Aim for a foot above the branch you are trying to clear. If you aim right for the branch, you will likely just hit the branch and not the air space above it, which is where you want the line to go – over the branch, not into it.


OK, so that throw didn’t go where you wanted. Flake the throw line back into the cube. Don’t just leave it lying on the ground and try to throw it as it fell. It’ll get caught on every piece of bark, every small stick, every clump of weeds, your boots – it’s going to get caught on everything if you try to throw it off the ground.

Hint: Keep your cube clean from debris. If there are a bunch of leaves and sticks in there, your next throw-line attempt will be rather humiliating.

Isolating a union

You’ve reloaded the line into your cube, reset your method and released the weight, and now the throw line sails cleanly over the branch above the one you were actually trying to hit. It happens. A lot. But all is not lost – you can manipulate the weight from the ground to isolate the branch below. Just get the weight swinging by pulling on the line to get some momentum. As it swings past the lower branch, let the weight fall on your side of the branch and bring the weight to the ground. Tie another weight to the other end of the line still in the cube and pull that into the tree. As the second weight reaches the top branch, carefully pull it over and maneuver it to the other side of the lower branch. Let the second weight fall to the ground, then tie on your climbing line. If this is hard to picture, see the demonstration of this technique in the accompanying video. (See link at end of article.) (Photo 6)

Photo 6: Maneuver the line by pulling and releasing.

Hint: When you pull the entire throw line through, take the time to work out little twists and knots.

Two cubes

There’s another method of isolating a limb, called double lining or double bagging, that uses two throw cubes. Throw the first line into a union above the union you want to use. Let the weight drop to the target branch and swing it so it flips over the target branch. Let the weight drop all the way to the ground, then attach the other throw-line weight to the first weight with a double-locking carabiner. The locking carabiner will prevent the gate from accidentally opening and getting stuck up in the tree as you pull it up. Pull on the first throw line to bring the double-bag system into the tree. You can manipulate it into place by pulling and releasing the throw line. All this becomes clear when you see a video.

Hint: When using two cubes, it’s a good idea to use two different-colored throw lines so you know for sure which line is over the limb.

The main idea behind using two weights tied together is that if a weight gets stuck, you can pull on the other line to try to get it out of a tight spot. If you get a single weight stuck in the tree, your only option is to try and yank it out. If it doesn’t break the branch, then the weight usually pops out with great force and can fly uncontrolled for a long distance.

Tie on the climb line

So the throw line is (finally) over the right branch, and you’ve retrieved the other end. Now it’s time to attach your climb line so you can start earning your keep. You’ll need a spliced eye on your rope for this trick to work. Clip a carabiner through the spliced eye and then onto the throw-weight ring. Pull the climb line up and, when the weight gets pretty close to that limb, give it a good yank, and the climb line will pop right over. Now we have our line up in the tree.

If your climb line doesn’t have a spliced eye, you can tie a pile hitch. Take a bight of throw line, put it in front of the rope, then wrap it behind and pull the loop over the end of the rope. Finish with two or three half hitches to keep the rope end in line with the throw line, then pull it into the tree. (Photo 7)

Photo 7: A pile hitch (bottom) with two half hitches at the end of the rope.

The main thing to remember about throw-line installation is that there are many ways to get a rope into a tree. Try as many as you can to see what works best in your situation.

Jake Carufel is a climber with Canopy Climber Tree Care in Burtchville, Michigan. This article is based on his demonstration of throw-line techniques in the TCI Magazine Test Kitchen at TCI EXPO ’21 in Indianapolis, Indiana, last November.

Tchukki Andersen, Board Certified Master Arborist (BCMA) and Certified Treecare Safety Professional (CTSP), is staff arborist for the Tree Care Industry Association.

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