Does all wild rose shoots have a pithy center? I found some today, really red in color, long, and notice that the thorns were at the tops of the shoots more so than all the way down it. After cutting, about 1/3 of the dia is a pithy substance. It is not mutli floral rose I know. Found it gowing in a field and some of the shoots are 6-7 feet long. Any idea what it might be? Did not have a camera so no pictures yet