Paulc, there lots of goldenrod species, I have been successful using what we call giant goldenrod, My personal experience when picking golden rod is to go big as they seem to shrink a lot while drying. As a rule of thumb you want your spindle to be about size of your little finger or roughly 3/8 to 5/8 " dia. when dry. I like length to be finger tips to arm pit to start, Golden rod worked pretty good for handrill fire but my favorite is horseweed. Hope this helps. Bob