Laboratory and greenhouse studies were conducted to determine the effect of temperature, pH, water stress, and planting depth on crowfootgrass (D. aegyptium) germination. When treated with constant temperature, crowfootgrass germinated over a range of 15 to 40°C, with the optimum germination occurring at 30°C (42%). Onset, rate and total germination (94%) were greatest in an alternating 20 and 35°C temperature regime. Germination decreased as pH increased, with greatest germination occurring at pH 4 and 5. Germination was reduced when seeds were subjected to water stress, and no germination occurred below -0.8 mPa. Emergence was similar when seeds were placed on the soil surface or buried at depths of 0.5 or 1 cm. Germination decreased with burial depth, and no seed emerged from 10 cm. These data suggest that crowfootgrass may emerge later in the season with warmer temperatures and after a precipitation event, and may emerge rapidly. These attributes could contribute to poor control later in the season by soil-applied herbicides or allow crowfootgrass to emerge after final postemergence treatments are made.