The effects of collecting season, collection site, laboratory pre-treatments and
temperatures on seed viability and germination of Juniperus macrocarpa were investigated.
Ripe cones were collected in four Sardinian dune systems, in two seasons, from plant and
soil. Warm (W) and cold (C) stratifications, two combinations of them (W + C, C + W), and
no pre-treatment (0) were applied. Seeds were incubated in a range of constant (10–25 8C)
and an alternating (25/10 8C) temperature regime. Seed viability was low (ca. 40%) and
varied significantly according to the collecting season. Seed germination was also low (ca.
10%), the 0 and W were the most effective pre-treatments on stimulating germination. The
best germination temperature, without any pre-treatment, was 15 8C (ca. 20%).
J. macrocarpa seeds are dormant and the achieved results suggested that the presence
of secondary dormancy is induced by cold stratification. Spring appeared to be the best
season for seed collecting, whereas autumn was the best for sowing. These results give
new findings for restoration activities on this species.