Stroke their velvety skins and notice how some are smooth, some are bumpy, and others are spiky. Study the lines of their crescent shape, curving back against the stems. In the fall, when the pods mature and begin to open, that elegant curve is filled with damp silk, attached to tawny seeds overlapping in a pyramid shape. Fall is also the time to harvest stalks to make string. Archaeologists judge that the invention of cordage, or string, enabled primitive humans to make an enormous leap in cultural evolution.
Primitive string is made from the inner bark of various fibrous plants.
Milkweed and dogbane are among the best cordage plants. If it works for you, let me know.