We conduct interdisciplinary research on long-distance nutrient transport in the phloem, leaf development, and the structure and function of plasmodesmata, the fine pores that connect plant cells. We employ molecular, physiological, and anatomical techniques in approximately equal measure. Our primary interest is in phloem loading, the active accumulation of sugars in minor vein sieve elements and companion cells. Loading creates the pressure that drives long-distance flow of nutrients throughout plants. One of our contributions to this area is the ‘polymer trap’ model that explains loading through plasmodesmata, long thought to be thermodynamically impossible. The polymer trap mechanism appears to have evolved at least five times. A large part of our current effort is in determining the phylogenetic distribution of phloem loading types in flowering plants and the ecological driving forces behind this evolution. The interdisciplinary aspects of the work make us one of the more collaborative labs in the department.