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Forest Research home > Research > Forest management > Regeneration and sustainable silviculture > Seed and seedling biology > Tree seed storage and pretreatment

Seed storage and pretreatment for Cedrus atlantica

Common nameCedar (Atlas)
Scientific nameCedrus atlantica
Storage characteristicsIntermediate (?)a
Storage moisture content and temperature9-12% @ < -5Ca
Dormancy characteristicsShallow
Pretreatment method8 (6-12) weeks cold (c. 4C)
See pretreatment of shallowly dormant species
Efficacy of pretreatment / remarksGenerally effective, a significant proportion of live seeds should germinate
Approximate date to initiate artificial pre-treatment (for 1 March sowing)4 January

Footnotes

Storage characteristics

Intermediate - seeds that can only be partially dried or need very slow, careful drying. They deteriorate more quickly than 'orthodox' seeds but more slowly then 'recalcitrant' seeds.

Orthodox - seeds that can be dried without harm, and once dried can be frozen, stored for years with little deterioration and relatively easily revived.

Recalcitrant - seeds that cannot be dried or frozen and are therefore short-lived.

(?) - indicates storage characteristics are not yet fully understood.

a Maximum advisable storage c. 3years @ c. 10% moisture content & -10C

Pre-treatment method

Figures in brackets indicate that different seedlots often require different pretreatment durations. There are three potential courses of action:

  • Adhere to the pretreatment duration in bold, with the knowledge that the maximum potential germination of the seedlot may be sacrificed for the sake of simplicity.
  • Inspect the pretreating seed regularly. Sow when c. 10% of seed is chitted, with the hope that this is indicative that the remaining seeds are now close to germination.
  • Inspect the pretreating seed regularly. At suitable intervals, remove chitted seeds (by hand, flotation, and/or sieving). Sow chitted seeds and return balance to pretreatment until no more seeds germinate.

Practice Guide

CoverRaising Trees and Shrubs from Seed (PDF-648K)

Forestry Commission Practice Guide 18.