Hey NTD I live down in sothern cali where arroe weed grows rampant. Im sure it will work for arrows however it is not the best. I heard it wasnt used for arrows at all. It i pretty straight but its kinda fragile. I dont recall having any succesful atempts. I will however recomend that you cut salt cedar it also grows in the same areas. Salt cedar aka tamarisk is exellent, I cannot emphazise enough, it is very durable and grows straight. If you do get the arrow weed however let us know how it turns out, im interested in seeing if you cna make reasonable arras.
Goodluck