Selecting crop and forestry plants based on growth performance is a very slow process, requiring as much as 5 to 10 years of observation under field conditions. This process limits the rate that a plant breeder or nursery person can select cultivars or clones with superior growth performance, adapted to particular climates andior stress conditions. Our methodology employing heat conduction calorimetry offers the opportunity to predict plant growth potential in specific environments in a matter of days. For full proof of concept of our ability to make short-term predictions of long-term growth rates of trees, we must examine additional species. For this purpose we will focus our studies on hybrid poplar and willow trees being raised for intensive agricultural production of biomass. Completion of these Phase I studies will validate the model and its feasibility for general application to a broad range of forestry, agronomic and horticultural crops in Phase II. The team of scientists on this project have unique experience in studying plant responses with calorimetry.Applications:Upon completing Phase I and Phase It of this project, we expect to have established the scientific basis and methodology needed to select plant materials and cultivars with maximum growth potential. adapted to specific temperature regimes and climates. Moreover. our methods will allow selection in a matter of days rather than years. This technology will then be provided to plant breeders and others selecting for superior plants, saving plant breeders and commercial nurseries millions of dollars in costs for developing superior new plant materials fit to very specific climatic and environmental conditions. It will be enormously valuable to USDA, State Agricultural Experiment Stations and others concerned with selecting and improving growing stock.