Tris waves for Colin to take the spade. "You're taller, they'll notice you first." Even if she has coppery hair, tall people are a bit more noticeable. And maybe it will keep one of Colin's hands occupied so he doesn't do anything too rude.

"I'll see if anything useful comes on the wind." With that somewhat awkward sentence, Tris slips her glasses off her nose and blinks into the breeze. If the wind passes over anything interesting on its way to her, she might catch it.