An automatically erectable decorative Christmas tree having a base, a telescoping center pole, a vertical array of curvilinear elements of graduated diameter supported from the top of the telescoping center pole by a plurality of circumferentially spaced tethers with the diameter of the curvilinear elements graduating in inverse proportion to the distance above the base; a plurality of circumferentially spaced branches pivotally connected to the curvilinear elements and extending radially outward from the curvilinear elements; and an electrically powered drive mechanism that is controllable by a user to selectively raise and lower the telescoping center pole. The subject tree can also be pre-lighted and pre-decorated. An automatically erectable support structure suitable for use as a tree stand and other applications is also disclosed.