i would think stratification is needed up here as we dont get a cold period for long enough or cold enough as you do down south,
Ah how do I explain this ? When I was suggesting that JBP may not need a stratification period ,then, even though we get cold here unless the seed is damp and placed out in the elements it would not get a cold stratification. Hence if I was to plant JBP seeds here without a cold stratification it would be the same as planting them without a stratification period north of here. Unless I planted in fall and was expecting a natural startification over winter. That is not what I am suggesting. I am suggesting germination starting as soon as they are planted.
I don't see any reason for it not to be the same yet anyway.
Checked the Reference Manual of Woody Plant Propagation by Dirr and Heuser
General notes for Pine state
Seeds of many species germinate satisfactorily without pretreatment, but cold stratification unifies and shortens the time required for germination.
So a commercial application will stratify as this would streamline operations. Yet there is advice that older seed will need a cold stratification period.
In temperate regions pine seeds can be sown in fall or spring. However, it is now common practice to spring sow non dormant species. Dormant seeds are spring sown after cold stratification.
It is a pity they did not expand on this as in non temperate zones but it does state some temperature figures in Lab conditions.
JBP and JRP germinates in fluctuating temps between 20 to 30 degree celsius
When fall sown JWP benefits from a few months warm stratification.
JBP benefits from late April to early may sowing.
JRP benefits from late fall sowing.
Some what confusing but thought that should be noted. Lets see what specific notes for each species states.
Oh and some notes on storage generally state seeds can be kept for a number of years depending on low moisture content and coldness depending on species but states nothing of how long they can be kept in damp conditions such as Jarryd has created at the moment. I figure working out which germination procedure to follow that allows for them to be planted in the near future taking stratification recommendations into account would be the best bet.
(JBP) Pinus Thunbergii.
Cones ripen April to May. Seeds disperse May to June.
Stored successfully for 11 years.
Fresh seed has no pre germination requirement.
Stored seed may require 1 to 2 months cold stratification.
In nursery practice seed is fall or spring sown after 1 or two months cold stratification.
Fall sowing produces better seedlings.
(JRP) Pinus densiflora
Cone ripens Feb- March
Seed dispersal March April
Can be stored for 2-5 years
Seed requires no pre treatment and can be spring sown.
(JWP) Pinus parviflora.
Cones ripen in April and disperses in May
Fresh and stored seed requires 3 months cold stratification. Sow outdoors in January february as this species benefits from a 2-3 month warm period.
From the above general notes that relates to JWP I am guessing this means it like 3 months warm stratification followed by 3 months warm stratification.
So I would suggest. 1 month cold stratification for the JBP and then sow while still warm enough. If I had enough seed I might do this (1/3 now) (1/3 1 month) and (1/3 2 months) and compare results.
Plant the JRP straight away. I think the temps now should see them germinate.
3 Months warm followed by three months Cold and plant in spring for the JWP.
Grant has done this on a nursery scale for many years so it will be interesting to hear his thoughts
Now I have some weeds to pull
