Knots for tying into mangroves

[team karst]

FWIW: I recently tied to an underwater round bar in a concrete mooring base. Used 12 plait 5/8” line, two turns around the bar then a bowline to allow quick release by a diver. There was a shocking amount of fraying. No wind storms no topside drama over those 2 days. Just swinging via current.

[RaymondR]

If one wishes to minimize chafe put the two wraps of webbing sling around the tree and shackle the ends together with the join close to the tree. Then use a largish bow shackle to fix the mooring line to the now endless sling with the pin through the eye and the bow around the sling. As the direction of pull changes the bow shackle will slide around the sling.

[Brocky II]

Originally Posted by valhalla360

I don't know what it's called but instead of tying the bowline loop around the object. Tie a bowline (or use a spliced loop). Pass it around the fixed object than feed the tail thru the loop. As you draw the tail up, it constricts.

We do it all the time when tying to a piling and then cleat the tail off on the boat.

If you are worried about it sliding up and down, you could pass the tail around and thru the loop 2-3 times creating something similar to a Kliemhiest or Prusick knot.

The Running Bowline can be tied around an object without having to feed the end through. Many arborists use it to tie onto branches.

[valhalla360]

Originally Posted by Brocky II

The Running Bowline can be tied around an object without having to feed the end through. Many arborists use it to tie onto branches.

Yes, I've seen that but typically, there isn't a great deal of movement and the tension tends to be fairly steady and no where near as strong as a boat in a hurricane.

The concern for this usage was that simply tying the bowline around the trunk does not constrict the knot, so the loop can slide up and down causing chafe.

By doing as I suggested, it constricts and thus shouldn't slide up and down eliminating the chafe concern.

[river]

I might use a "no knot" or tensionless hitch.


https://en.wikipedia.org/wiki/Tensionless_hitch


The carabiner is optional. You can also tie it as a many turns and two half hitches. The important point is that the load is taken by friction on the tree. The finishing knot just keeps it in place.

[Cheechako]

Originally Posted by tkeithlu

Ditto on RaymondR's advice. If you are not up for rigging that and need to tie a knot, remember that two half hitches makes a constricting loop while a bowline makes a fixed loop. If I was tying to a single tree trunk, I'd be inclined to use a clove hitch sealed with a half hitch. The loss in strength is then low and I doubt that it would chaff.

I'd do this^
You want the tie to not slide or move. A clove hitch will constrict.

[Hasbeen]

I have spent half a dozen cyclones up mangrove creeks in the Whitsunday Island area of the Great Barrier reef. I was responsible for 5 company boats, & my own yacht, & we had 3 other company boats each with their own skipper.


We always tied out to 4 mangroves for each boat, 2 ahead & 2 astern, with a line connecting all boats bow to stern, to allow movement between boats when flood run in the creek was faster than a dingy outboard could manage. My speedo topped at 12 knots on one occasion.



We always tied a big loop around the mangrove with a bowline, & never had a problem, or damaged a tree.


Make sure you have plenty of free line at the boat. We found the water in the creek would rise at least 10 Ft & on one occasion it rose about 15Ft.


We never had a problem with wind speed, although 90 knots was often recorded just a few miles away. Our biggest problem was sandflies, [midges], & mosquitos, who invaded the boats.

[merrydolphin]

Certainly, a full round turn is needed to spread load and chafe. No matter the finishing knot. As a rock climber there was only one knot that we would bet our life on, and a bowline is not one of them. The knot trusted with our life is the retraced figure8. The reason is all of the parallelism through out the knot. Parallel friction is what holds in knots. And the round turn first spreads loads.

No, it is not adjustable. You would probable adjust from the boat is staying aboard.

[thinwater]

Originally Posted by river

I might use a "no knot" or tensionless hitch.


https://en.wikipedia.org/wiki/Tensionless_hitch


The carabiner is optional. You can also tie it as a many turns and two half hitches. The important point is that the load is taken by friction on the tree. The finishing knot just keeps it in place.

^^ I'd like more discussion of this. Climbers use this method for anchors all the time, to prevent chafe on tree bark. I've made most of my top rope anchors this way for 50 years (yes, I've been climbing that long, including yesterday). The trick is to use at least 4 turns. The tree needs to be at least 4 inches in diameter for it to work well. There will be zero wear on the rope.

[jo_sail]

Originally Posted by Jamme

Could that be avoided by simply doing two turns around the tree before closing the bowline?

Yes right,

best used on the mangrove as:
Very long version of Ashley Book of Knots, #1012, Water Bowline with 1.5 round-turns

Find instruction (German text) with detailed photos placed at the bottom here: http://www.skipperguide.de/wiki/Fest..._an_einer_Boje

This is recommended e.g. in The Complete Ocean Skipper by Tom Cunliffe in section Moorings page 217-218 for tying to a buoy and for avoiding chafe:

1.5 round-turns „triple the bearing area“ compared to a simple bowline. Movement is reduced to a minimum.

You could do more round-turns, if you feel you need it. But coming loose will be less easy with additional round-turns. The round-turns already apply some constriction (similar like the initial turns on a bollard, but not as much as the clove hitch).

I think 1.5 or 2.5 round-turns are a good compromise between too much of constriction (which will damage the bark as well or constrict sap flow in it as discussed for slack lines on tree trunks) and enough constriction to reduce chafe significantly (protecting the bark of the mangrove from chafe, or the rope when fixed to the rusty steel ring of a buoy).

In storm conditions likely any tie will not be good for the mangrove (again like discussed for the hard tension of slack lines on trees), anyhow it is not wise to go to the mangrove, and it would only be an emergency solution to rely on tying with several lines to different mangroves.

Cheers Jo

[RaymondR]

"In storm conditions likely any tie will not be good for the mangrove (again like discussed for the hard tension of slack lines on trees), anyhow it is not wise to go to the mangrove, and it would only be an emergency solution to rely on tying with several lines to different mangroves."

Why, my insurance states that for coverage to apply during a "named storm" which generally only applies to tropical, revolving storms, the vessel must be either in a properly rated marina or in the mangroves.

One assumes that in the mangroves applies to a place, such as a mangrove lined creek, where there is considerable protection from wind generated waves and some lessening of wind strength.

The experience in Australia is that marinas are not exceptionally secure havens from extreme weather events and in places such as Cairns in northern Australia where the marina is very exposed it is a requirement that the marina be abandoned and all vessels be moved up into the mangroves to assigned anchorages therein.

In the case of cyclone Yasi which passed over the marina in Cardwell about the only vessel which survived undamaged was one which was taken from the marina up into the mangroves and anchored.

As to damage to the mangroves, whilst one should avoid any environmental impacts, they are very aggressive colonizers and any which are damaged would be fairly rapidly replaced. I regularly anchor in a tidal river which floods due to tropical rain events which drown the mangroves and many of them subsequently die but are replaced with adult plants within a short period of time.

[ahun]

Scaffold knot.

[s/v Jedi]

Marinas in Port Canaveral are all evacuated and boats move a couple miles inland in the mangrove lined Canaveral Barge Canal. We get “tree savers” from Tractor Supply to wrap around the roots and tie our lines to. These have a loop on each end, making it easy.