Tara Donovan works wonders with the most basic, low-budget materials—toothpicks, straws, paper plates, etc. The two sculptures in her current show are as eye-poppingly impressive as her other site-specific sculptural installations. In one piece, an accumulation of millions of stacked index cards looks like a mountain range, or, thanks to its bluish tint, a collection of icebergs. The other incorporates thousands of short acrylic rods (similar in size and shape to drink stirrers) into clusters of spherelike poufs—think dandelion heads, or a growing organism viewed under a microscope. The artist has a larger, concurrent show at Pace Gallery in Menlo Park, Calif.