Ephedra Seed Germination1

Abstract Germination of seeds of gray ephedra ( Ephedra nevadensis Wats.) and green ephedra ( E. viridis Cov.) must be better understood for propagation on southwestern rangelands of the United States. Investigations were conducted on germination of these species in a wide range of constant and alternating temperature regimes and in different osmotic potentials. Both species germinated over a relatively large range of temperatures. Optimum germination for gray ephedra occurred at constant temperatures ranging from 5 to 20 C and at alternating temperatures of 20/25 C. Green ephedra had optimum germination when combinations of 16 hours of cold temperatures (2 or 5 C) and 8 hours of moderate warm temperatures (15 to 25 C) were followed. Gray germinated faster than green ephedra. Seed storage at room temperature for 12 months after maturity reduced germinability (drastically in the gray ephedra). Low osmotic potentials (created with NaCl or polyethylene glycol) reduced germination more in the green than the gray ephedra seeds. Germination of both species should not limit their use in revegetation except on salty soil in the case of green ephedra.