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Cheatgrass seeds germinate readily and usually near 100% shortly after collection. Generally, practically all seeds that fall to the ground germinate and plants emerge with favorable conditions in the fall, during the winter, or in early spring. In this study, an average of 692 cheatgrass plants/ft2 emerged the first year. In the same soil samples, 273 seeds/ft2 did not germinate but produced plants when these seeds were brought into favorable conditions in the greenhouse. When these ungerminated seeds remain in the soil-litter mass in the field, they germinate and emerge more slowly than seeds brought into the greenhouse. Seeds that remain in seedheads over winter germinate slowly but with a high percent when placed in a germinator. Nitrogen at 80, 160, 320, and 640 lb/acre caused the number of plants that emerged in the field to decrease slightly as the rate of fertilizer increased.
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Hull et al. (1974) studied this question.
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