Does anyone know if there are shade-tolerant species of cold-hardy pine trees that produce pine nuts? I'm getting different answers from my Google searches. I've seen some pages that say they are shade tolerant, while others say not to plant them in the shade. Most pages say that they need shade as seedlings to survive, and many warn against moving them into the sun too quickly.
Maybe they will grow slowly in the shade but need to reach sunlight before they will start producing cones? I know that the natural succession for forests around here is for spruce trees to grow slowly under the birch trees until they eventually break through the canopy and in turn shade out the birches.
I'm sure it probably depends on the species. I've been looking at Pinus sibirica (Russian Cedar/Siberian Pine) and Pinus koraiensis (Korean pine) for their cold tolerance. I live in a quite cold area (USDA hardiness zone 2) that gets fairly warm in the summer. I've read various cold hardiness estimates for the Korean pine, so maybe there are some that are better adapted to the cold than others. One page said that they will grow just about anywhere that white spruce will, and white spruce is definitely shade and cold tolerant.
I live on ~1/12 acre urban lot and right up against the property line on the south side the neighbor has a bunch of very large spruce trees. The back yard is long but narrow (~ 60 feet north to south, ~15 feet east to west). There is a seven foot fence and a single-story house to the east and a single-story house to the west. This has created quite a shaded area in the southern half of the back yard.
It can't be completely shaded, as there are a few trees (including a small birch) that are growing back there. I think it gets a little bit of sun down low from the East and West, and if the tree gets high enough it would get quite a bit of sun from the East and West. The trees growing there are actually stretching North a little bit, and during the summer we do get some low light from the North.
I was thinking maybe a pine nut tree and some blueberries and/or huckleberries might be good to put back there. Do you folks think that would work out? Any other suggestions for things to plant would be welcome.