@Cerauno - Hello, I have some experience starting white pines from seed. I have raised batches, or at least got germination with Pinus flexilis, lambertina, parviflora (JWP) bungeana, and edulis. I lost all the limber pines and sugar pines to damping off, but I did get good germination. My humid summers and too shady a spot caused the damping off. Pinus albicaulis - Whitebark, is very much in the same group and seed should most likely require the same treatment. My JWP, and Lacebark pines are finishing their 3rd summer.
All members of the white pine group have seeds that do not store well. About 18 months dry and cool, and viability will drop below 50%, and at 3 years will be a percentage down into the single digits. So plant your seeds this fall. Get the stratification process going. When you have fresh seed that has not dried out, some seedlings will germinate immediately. The majority will need first a summer ''warm'' stratification of 60+ days and then a cold stratification of at least 90 days. The natural method is to plant them in a flat, keep them outdoors, and do not disturb the flat for 2 full summers. I use Anderson flats, 15 x 15 x 5 inches, with mesh bottoms. I construct a 1/4 inch mesh hardware cloth (wire mesh) cover and tie it securely to keep out squirrels and varmints. Absolutely necessary in my area. Seeeds emerge through mesh, end of second growing season they still have no branches so it is easy to lift the wire top off. For deciduous seedlings, wait until autumn after leaf fall and the mesh will lift off easily. Without the wire screen, you will just be feeding squirrels and birds.
Planted in autumn, usually a few sprout the next spring, then the second spring another percentage will sprout. If you don't want to leave a flat for 2 years, plant seed in spring, and then by the end of the following summer most that will sprout will have done so. It is a pain the behind, but really, you won't know what you will get for 2 full growing seasons.
Full sun, and good exposure to air, a breeze is your friend, otherwise damping off is a problem.
By the way there are no legal issues collecting seeds or trees from private property if you have land owner's permission, at least in the USA. Pinus albicaulis while conscensus is that it is either threatened or endangered has not been listed by USDA as Endangered, because they claim to not have adequate funding to meet requirements if it does get listed, so it is not ''officially'' listed in the USA, but it is Listed in Canada. So collect all you want from your brother's land. As long as his land is in the USA, no problem.
Since you are in Montana you have a good shot at being able to grow it, It is a species that will likely not do well at low elevations, in the warm humid eastern and southeastern parts of the USA. High temps, especially at might are rough on this species. This is true of many mountain species, They can only take heat if nights still get cool. How cool, I don't know the ''magic number, my guess if you don't drop below 65 F most of the time at night, you won't be able to keep it happy.
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