"Hmm." It was a noncommittal sound as Cross craned his neck around to look at the vines again. He didn't know a great deal about vines or foliage of any kind, really... except maybe kudzu, which was ever-present in the South where he'd been born. Seemed a strange behavior for a vine, though, particularly the hardening. He'd thought vines were always flexible. He didn't seem to get in any hurry to continue the train of thought, but took a couple more minutes to look and formulate his thoughts before turning back around. "Guess we'll figure it out," he said mildly.