To answer many of the major questions in comparative botany, ecology, and global change biology it is necessary to extrapolate across enormous geographic, temporal and taxonomic scales. Yet much ecological knowledge is still based on observations conducted within a local area or even a few hundred square meters. Understanding ecological patterns and how plants respond to global warming and human alteration of landscapes and ecosystems necessitates a holistic approach. Such an approach must be conducted at a scale that is commensurate with the breadth of the questions being asked. Further, it requires identification, retrieval, and integration of diverse data from a global confederation of collaborating scientists across a broad range of disciplines. We propose to network core databases and data networks to create a novel resource for quantitative plant biodiversity science. The grand challenge is to assemble and share the world’s rapidly accumulating botanical information from plots and collections to create a distributed, web-accessible, readily analyzable data resource. With such a resource, we will answer major questions of direct relevance to plant ecology, plant evolution, plant geography, conservation, global change biology, and protection of biodiversity and ecosystem services. In particular, how does climate influence the distribution and abundance of plant species, how does the phylogenetic diversity of plants vary across broad environmental and climatic gradients, and how are plants assembled into ecological communities? While these and associated questions are at the core of many research endeavors in comparative botany and ecology, our past collective inability to integrate data on a large scale has significantly limited our ability to address these questions head on. This proposed Grand Challenge team will create a data resource of unprecedented size and scope together with the tools for its use, thereby empowering botanists and the general public to better address fundamental issues in plant ecology and global change biology. Although we will focus on plants of the New World, the infrastructure and protocols developed will be scalable to all geographic regions and all types of organisms. Future steps will enable cross-cutting linkages to emerging networks on plant genomics, physiology, and phylogeny, allowing us to address fundamental genetic and evolutionary questions at unprecedented spatial and temporal scales.