Abstract: A stand including a square vessel in which the trunk of a Christmas tree is clamped and held, has a pair of clamping screws extending inward from its opposite corners, along a common diagonal axis. The inner ends of the clamping screws have narrowed necks over which fit slotted clamping angles, whose bottom ends are slotted upwardly to fit onto a diagonal rib in vertical registration with the clamping screw axis. As the screws are advanced inwardly the clamping angles are guided and stabilized by the rib, to maintain parallelism with the square corners of the vessel.