Rewild Portland is a non-profit organization in Portland. www.rewildportland.com
They recently posted a workshop description that was very enticing. Unfortunately, I had a schedule conflict.
"Rubus armeniacus, or as we call it Himalayan Blackberry, is a plant that despite its common name is native to Armenia and North Iran. Over the period of European colonization of North America, this plant has become a serious invasive. Its rigorous growth and thorny vines makes it a pain to remove. Its sweet and delicious berries are eaten by many animals, thus spreading its seed quickly and efficiently. We are happy to say that we have found a use for this plant (other than eating the berries) that will encourage more of its removal: its strong and durable bark provide a great material for weaving!"
So I arranged for a workshop in Eugene with my weaving friends, taught by Peter Michael Bauer. We had a lovely day gathering, prepping and weaving with out new material.
So here are the differences, as described by Wikipedia
-thorns are derived from shoots
-spines are derived from leaves
-prickles are derived from the epidermis (so they can be found anywhere on the plant, and don't have vascular bundles inside so they can be removed more easily and cleanly than thorns and spines