Anything being called a [seed] strain carries the implication of at least some consistency of characters.

All is possible with seed strains within reason. I am assuming you are referring to Picea abies. I am not familiar with a Blue strain, but there could be one. And with enough time you could develop your own strain.

In the late 1800's or early 1900's (I forget), Seeds of Abies procera from the West Coast were planted in Denmark. From those seedlings the Bluest were selected and planted out into a seed orchard. Those crossed pollinated and the seed produced was planted out into another seed orchard. All the time the greener trees within the orchard and those with undesirable characteristics were eliminated. Fast forward 80-100 years of doing this over and over again and there are now several different orchards in Denmark producing seed that is Very Blue, and also slower growing, characteristics that were the most desirable. Similar orchards have been planted all over the world of different species to obtain certain strains that are the most desirable.

We have an orchard of Abies procera that is selected to produce the highest percentage of good quality Christmas Trees. They are also resistant to a needle scorch that can sometimes destroy a crop on a bad year. Also fuller and sometimes faster to market.

Kind of fun encouraging mother nature to give you what you want with a little cross pollinating and careful selection.

Only one person comes up in my mind when I was reading this story.
Last winter I heard the same story in person from the man himself... :0)

You are a good listener. I am still not aware of a Blue strain of Picea abies. I did some work with another guy who was developing a Blue, compact strain of Abies lasiocarpa.

Very interesting stuff. Too bad its a very long term investment.

How about this one:
This is a most interesting cross between an Abies koreana and Abies lasiocarpa.
It would be very nice to see how it's seedlings would be develop.
I bet from this one could be made a very interesting strain of nice compact Abies lasiocarpa specimens...
Abies koreocarpa 'Inga'