As I discovered yesterday, stinging nettles are an absolute pain to process. First of all, while breaking them, I discovered a rather large number of tiny, green insects living on its bark which demanded quite a bit of labour not to crush. In addition, their fibres are brownish and rather short, often ending whenever the next node came about. Unless you live near a gorge filled with them, they are likely not worth your time.
Later that day, on a walk, I came upon a patch of wood nettles and decided to try the same with those. Their soft, watery stems flattened readily, requiring little effort in the lower sections and slightly more higher. A more severe angle was required to break their woody stems due to their flexibility, but they peeled away readily after that. Once I began to agitate the fibres and bark, though, I soon found that they were of a much higher quality— softer, lighter in colour, and longer, generally— most of the fibres were at least a half a metre long.
I may just be terrible at plant identification and have stumbled upon a ramie patch, but I imagine it would be rather uncommon in my area.