Cordage

Nettle (Urtica dioica) stems, dogbane, milkweed, the inner bark of lime/basswood and willow, and the leaves of yucca and agave all give strong cordage.

Test before harvesting in quantity: strip a thin piece and twist it hard between your fingers, then bend the twist double. Good fibre stays whole. Brittle fibre snaps. Confirm the species against a regional guide — see the fibre guide — and wear gloves for nettle and agave: nettle stings until dried or retted, and agave sap raises blisters.

• Nettle, dogbane, milkweed: late summer to winter, when stalks have died back and dried standing — they are partly retted by weather already. Nettle stems 1–2 m tall give the longest fibre.
• Lime, basswood and willow inner bark: late spring and early summer, when the sap is running and the bark peels off in long strips. Take bark from coppice poles or fallen limbs rather than ring-barking a standing tree, which kills it.
• Yucca and agave: mature outer leaves, any time.

Strip leaves from nettle by pulling a gloved hand downward along the stem.

Dew retting: spread stems thinly on grass, turn weekly, 2–6 weeks depending on warmth and damp. Water retting: submerge bundles in still or slow water, weighted, 1–3 weeks — faster in warm water.

Test daily once it starts: rub a stem between your fingers. Ready when the fibre peels away cleanly and the woody core snaps crisply. Over-retting rots the fibre itself and it goes weak. Bark strips for lime/basswood cord soak 2–4 weeks until the layers slide apart.

Retting is not optional for bast and bark: green fibre shrinks as it dries, the twist loosens, and pith left in the cord rots it from inside.

Dry the retted stems fully. Break them by crushing along their length — a mallet on a log, or bending over a blunt edge — until the woody core shatters into short pieces. Scutch: scrape and beat the broken stems with a blunt wooden blade to knock the woody chaff out. Hackle through a comb of nails set in a board to straighten the fibre and remove short tangles.

What is left should be clean, long, parallel fibre with almost no woody fragments.

Take a bundle of fibre the thickness of the cord you want and fold it about a third of the way along, not in the middle, so the two ends run out at different points.

1. Twist the far strand away from you, tightly.
2. Cross it over the near strand toward you.
3. Repeat with the new far strand.

The individual twist in each strand and the opposite wrap between them lock each other — that counter-twist is the whole of the strength. Keep every twist the same tightness; loose spots are weak spots. A good cord, slackened, tries to kink back on itself.

Add new fibre when a strand is about 5 cm from running out: lay a tapered bundle alongside the thinning strand, overlap it 5–8 cm, and twist them together into the same strand. Because you folded the first bundle off-centre, the two strands run out at different places.

Never join both strands at the same point — that is a guaranteed break. Trim the tufts of fibre that stick out once the cord is finished, not while making it.

For rope, make three cords all twisted the same direction, then lay them together in the opposite direction. For heavier rope, lay three of those ropes together the opposite way again. Every level reverses.

Plying shortens the material — allow roughly a quarter to a third extra length in the strands. For long ropes, a simple rope walk — hooks on a crank at one end, a grooved wooden top between the strands to keep them apart as they lay — gives even lay over many metres.

Hang a container from a length of the cord and add water a litre at a time — a litre is a kilogram — until it breaks. That is the breaking load.

Use cordage at no more than a fifth of that for anything routine, and never trust untested cord for a load on which a person's safety depends. Store cord dry and out of sun; wet plant cordage rots and sunlight weakens it. Make cordage constantly, in the gaps between other work — see the knots guide for what to do with it.