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Store moist @ 4°C
12 (8-16) weeks cold (c. 4°C)
Generally effective although pretreatment durations, and numbers of repeat cycles may vary significantly between seedlotsApproximate date to initiate artificial pre-treatment (for 1 March sowing) 6 December
Recalcitrant – seeds that cannot be dried or frozen and are therefore short-lived.
Figures in brackets indicate that different seedlots often require different pretreatment durations. There are three potential courses of action:
Raising Trees and Shrubs from Seed (PDF-648K)
Forestry Commission Practice Guide 18.
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