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Laboratory experiments were carried out to examine the effects of temperature, irrigation and the depth of seed burial in sand on seed germination and seedling emergence of Astragalus adsurgens Pall. and Melilotus albus Desr. ( Fabaceae), which are herbs often used to rehabilitate desertified sand dunes in China. Seeds of both species germinated well between 5 and 35 degrees C, indicating that temperature is not a determinant of seed germination in the field for either species. For both species, seedling emergence from sand was favoured when seeds were buried at depths of 5 - 30 mm. Because an increase in the amount of irrigation resulted in a higher moisture content in sand and persistence of moisture in sand for a longer period, a larger amount of irrigation resulted in a larger number of seedlings emerging. Seedlings stimulated to emerge by a larger amount of irrigation survived for a longer period. It appeared in the field that light and infrequent precipitation in spring would result only in futile germination of buried seeds, and that frequent and relatively heavy precipitation in the summer rainy season would enable seedling establishment of these species.