Timber Rebirth December 30, 2016 4352 × 2392 New wood technology may offer hope for struggling timber This Nov. 15, 2016, photo shows a piece of cross-laminated timber, or CLT , in Portland, Ore. CLT is made up of 2-by-4 beams laid out in perpendicular layers that are then glued together to make giant panels. (AP Photo/Don Ryan)