Imbibition and germination of seeds of threeAcaciaspecies from Ethiopia, namelyAcacia nubica, A. seyalandA. horrida, were tested in laboratory conditions. Heat treatments had a positive effect on imbibition rates for all three species. The best treatment was 60#xB0;C for two hours, a longer time of exposure having a negative effect on the seeds. A positive response to light was detected inA. nubicaandA. seyal, while seeds ofA. horridaresponded with indifference to light. A high degree of hard-seededness#x2014; over 90#x2014;was common in all three species. Although temperature had a positive effect on germination rates, only scarification of seeds proved to be effective in overcoming hard-seededness.
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