The Triticeae Toolbox Oat (T3 Oat) is the repository of oat phenotype and genotype data for the Global Oat Genetics Database. The Triticeae Toolbox (T3) is the web portal for data generated by the Triticeae Coordinated Agricultural Project (T-CAP), funded by the National Institute for Food and Agriculture (NIFA) of the United States Department of Agriculture (USDA). It also contains data from US Uniform Regional Nurseries, supported by the US Wheat and Barley Scab Initiative. The database was initially developed as The Hordeum Toolbox (THT) to hold barley data generated by the Barley CAP project (2006-2010). T3 Barley hods data generated for Hordeum vulgare L. T3 Wheat holds data generated for Triticum spp. T3 Oat holds data generated for Avena. All are being enhanced in database performance, community curation and user tools. T3 contains germplasm line information, pedigree, genotype and phenotypic data from breeding programs participating in the CAP and core germplasm collections maintained by the USDA National Small Grains Collection.