Examples: Most conifers (e.g. firs, pines and spruces).
A few broadleaves (e.g. alders and birches).
All these seeds (whether freshly collected or dry-stored) are slow to germinate and/or only capable of germinating over a narrow range of conditions until pretreated. Pretreatment usually consists of incubating seeds for a relatively short period of time (3 to 12 weeks) under moist conditions at c. 4°C (a so-called prechill).
There are several potential methods which can be used to pretreat shallowly dormant seeds. Three are described below:
Easy: Natural (outdoor) pretreatment/germination with medium for deeply or shallowly dormant tree seeds
Moderately easy: Artificial (temperature controlled) pretreatment/germination with medium for deeply or shallowly dormant tree seeds
Skilled: Artificial (temperature controlled) pretreatment without medium for deeply or shallowly dormant tree seeds.