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The Great Basin of North America has been identified as an area that suffers from elevated levels of degradation, and is difficult to restore via seeding practices. Seedbed freezing conditions during the winter have been shown to limit seedling establishment. Mortality may also occur over the winter period to seedlings from drought, pathogens, and expenditure of seed food resources. Hydrothermal models have been used in the past to effectively predict when seeds will germinate. By understanding when seeds will germinate during the year we can further understand what limitations affect seedling establishment and develop restoration practices that can help seedlings overcome these barriers. We germinated seeds from 10 different native species in the Great Basin at 5, 10, 15, 20, and 25 ?. From germination count data, thermal-time germination models were calculated using a new Microsoft Excel workbook we developed called �Auto-Germ.� Auto-Germ uses germination count data obtained from laboratory trials performed over a range of constant temperatures to calculate thermal-time germination models and a suite of other germination indices. Auto-Germ also provides the user with an interface to apply the thermal-time germination models to estimate germination timing from simulated planting dates. Models developed from the species test in our trial had sufficient accuracy (R2 = 0.60- 0.98) to predict germination timing. The application of these germination models to historic soil moisture and temperature data over a 6-year period across 10 sites throughout the Great Basin indicated variation in germination timing between the species. Most species germinated rapidly, within fall to early winter period, which may limit their survival. These results indicate that more research should be conducted to understand how germination timing influences seedling survival and if practices could be developed to either push germination to more suitable conditions or help seedlings overcome environmental barriers.