The human animal has been using cordage for thousands and thousands of years; and contrary to popular belief, those grizzled ol’ branch managers, with their black coffee in one hand, a pinch between their cheek and gum, and a rigging line in the other hand, have not been there every step of the way.
The reality is that human folk have been tying knots and splicing cordage for longer than any current memory. Along the way a wide variety of methods for attaching something to the end of a line have been developed and tried. Some have been forgotten or not passed along, while others are almost as ancient as the use of cordage itself. All of these methods have one goal: securing something, or someone, to the end of a piece of cordage in a safe, secure and efficient fashion.
Along with this extended history of cordage use, and its attendant knots, hitches and splices, comes its own version of folklore, myths, legends and hotly contested opinions. While experience certainly has value, and opinions may have some merit, one does not benefit from repeatedly having bad experiences or relying on opinions that are based on whimsy rather than data. Modern tree professionals have far too many sources of accurate, scientifically tested information on rope strength in regard to hitch, knot, splice and stitch choices to base these decisions on what the ol’ grizzled branch manager mutters in between sips of coffee, curses and spitting.
The three primary factors that should be considered when choosing a knot, hitch, splice or stitch for use at the end of the rope are safety, security and efficiency.
Safety is the strength loss created by the chosen knot or splice. Sharp bends in a rope decrease its strength, thus an attachment method requiring sharp bends will be inherently weaker, or less safe.
Security means the interaction of the hitch or stitch with the connecting link or item being attached. Carabiners are strongest along the major axis, and are intended to be loaded this way, thus an attachment method that does not stay in place is less secure than one that does stay in place during the various movements when climbing. Snap hooks or snaps retain roughly the same amount of strength as long as the attachment method is through their captured eye, thus a method that is less secure might be acceptable when using them, as movement within the captured eye does not radically reduce a snap hook’s strength. Using a knot or splice that is not secure on a large piece of woody debris is a good way to end up with a crew member in the ER, thus security plays a role even in rigging scenarios.
Efficiency is how easy is it to use a particular attachment method, how difficult and how long does it take to attach and detach with the chosen method in the case of personal support, or in the case of rigging, tying off and untying the piece? Methods that are more quickly attached and detached from are obviously more efficient.
Original forest gangsta style
A variety of knots and hitches are used for attachment/personal support and rigging, whether it be the end of a climbing line, a split bridge/tail in a dynamic climbing system, to secure a connecting link to the end of a work-positioning lanyard, or to tie off a piece/branch when rigging. All of these knots and hitches will cause strength loss due to the creation of bends in the rope, however, some will create more strength loss than others.
Traditional choices for a termination or attachment knot at the end of the climbing or rigging line have been the clove hitch or the bowline (straight or running), both of which should be backed up in some fashion, particularly when used in a split tail/bridge system. In a traditional system, in which the tail exiting the clove hitch or bowline forms the climbing hitch, a figure eight and the climbing hitch itself forms the backup. More recent attachment or termination knots and hitches include the Buntline hitch, the Anchor hitch and the Triple Fisherman’s or Scaffold knot.
The ones that cinch down on the connecting link securely, such as the Buntline or Scaffold, are a better choice when using carabiners, due to possible cross or side loading of the carabiner. In regard to rigging, there is a wide variety of hitches used, traditionally the Running Bowline or Clove hitch with appropriate backup as required, but once again the problem is in the bends, all will have some strength loss, somewhat dependent on what type of line/rope is being used.
As knots and hitches, all of these choices require more time than some other methods to attach and detach, necessitating the correct forming of the knot whenever it is necessary to move over or around a branch, reset the tie-in point, or tie on or untie the piece.
Art + science = spliced eye
The method used to create the splice will differ depending on the construction of the rope being spliced, but all splicing by hand relies on the beautiful property of friction to function correctly. This attachment/termination method is also used in a variety of personal support applications, including the ends of climbing lines, split bridge/tail systems and work-positioning lanyards, but can also be quite helpful and strong in the end for rigging lines.
Hand-spliced eyes may be small, tight eyes that grip the connecting link securely or larger ones in 16-strand lines that are girth hitched around the connecting link for security. Eyes in the end of rigging lines are typically larger so they can be girth hitched, though small eyes are certainly applicable with the use of snap hooks or rigging carabiners for special applications.
An absence of sharp bends in the rope makes a correctly formed hand-spliced eye much stronger than any knot or hitch; and the ease of attachment and detachment from carabiners or rigging loads increases efficiency. However, small, tight eyes hand-spliced through the captured eye of snap hooks will prevent their removal entirely. A larger eye that is girth hitched through the captured eye would give the climber the option of detachment.
Stitchin’ is bitchin’
Industrially stitched eyes in the end of climbing or rigging lines is fairly new to tree care, but the method has been used previously in other industrial and recreational applications. The rope is simply stitched back to itself to create the desired size of eye, though stitch count and pattern are typically, and needfully, specific to certain types, constructions and fibers of rope. This method reduces sharp bends in the rope immensely, and thus causes the least amount of strength loss of any method discussed here. In addition, the eyes formed may be as small and tight as possible, allowing for secure and efficient placement on a connecting link, such as a carabiner.
As with hand-spliced eyes, industrially stitched eyes through the captured eyes of snap hooks will not be removable, thus reducing their ease of use with that particular connecting link. Unlike hand-spliced eyes, industrially stitched eyes are not commonly available in larger eyes for girth hitching of climbing lines due to the core remaining inside the rope in the stitching process, thus preventing a secure grip when girth hitched onto the connecting link. However, the use of industrially stitched eyes does allow for eyes in the ends of some ropes that are extremely difficult, or impossible, to splice due to their construction. Larger eyes can be industrially stitched in rigging lines, as the presence of the core typically is not an issue in such applications.
Whatever choice is made, whether it be knots or hitches, splices or stitches, each and every one will have advantages and disadvantages in particular applications. What’s important is not which choice a climber or crew member makes, but that their choice is an informed one based on the science and reality of the method, not the folklore and opinion surrounding it. The basic information discussed here can help make those daily choices not only informed ones, but safer, more secure and efficient ones.
Editor’s note: This article was originally published in September 2014 and has been updated for accuracy and comprehensiveness.