Usually, at least for me, I never really bother to find out exactly what something is. If goldenrod can make an arrow, then most things will
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(or at least in my way of thinking
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). As for striaghtening, just gather some shafts, debark then and cut them to length, then everyday go over them with a hard stick to "rub the bends out", stating at the back and striaghtening the arrow from there. Tip gleaned from Ken Wee's articles in the first few PA's
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and John McPherson's article on Primitive arrows in a more recent PA. They're easier to striaghten (especially bigger shafts) and tend to stay striaghter.
A good arrows worth a hundred good bows
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.