Seed storage and pretreatment for Sorbus torminalis

Common name Service tree (Wild) or Wild Service tree
Scientific name Sorbus torminalis
Storage characteristics Orthodox
Storage moisture content and temperature 10-12% @ < 0°C
Dormancy characteristics Deep
Pretreatment method 2 (2-4) weeks warm (c. 15°C) plus
30 (16-30) weeks cold (c. 4°C)
See pretreatment of deeply dormant species
Efficacy of pretreatment / remarks Generally effective although pretreatment durations, and numbers of repeat cycles may vary significantly between seedlots
Approximate date to initiate artificial pre-treatment (for 1 March sowing) 19 July


Storage characteristics

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

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.