I'm not aware of any commercial sources. Sheffield Seed Company lists their source as "China", but I doubt it comes from an improved seed orchard. You could contact them to see if they know anything about the genetic quality of the seed:https://sheffields.com/seeds-for-sale/Robinia/pseudoacacia///////13... Years ago the seed they were importing came from Germany, where it was being propagated in seed orchards to produce economical seed for aerial mine reclamation. Judging from what's growing here on the farm, the form doesn't strike me as anything special.
I've attached an article below on Black Locust improvement in Hungary. Peter Smallidge (Cornell's state extension forester) was able to import a small amount back in the summer, and has been working with the NRCS Plant Material Center in Big Flats, and the manager of Cornell's greenhouses to propagate the seed. Germination so far has been poor (the Hungarians warned us ahead of time that this was the case).
We also collected root cuttings from a number of "superior" trees a few years ago, but it's hard work digging cuttings - and even harder to get them to grow. I would recommend this method only to clone a truly superior tree.
My advice would be to seek out particularly straight parent trees in the area and try to collect seed from them. This is a good time of the year as the pods and small limbs are usually littering the ground. Immerse the seed in hot water and let soak overnight before sowing.
I am looking for a Black Locust Seed source also. I am not as worried about the specific genetics (at least not yet) as I am testing another theory on establishment.
I am hoping to establish silvopasture into several 10 acre pasture paddocks by drilling the seed in with a no-till seeder. Based on the impressive first year growth from my seedling black locusts, I figure I can save a ton of labor (and likely some costs) if I can find a reasonable source for seed.
I figure I can protect the seedling rows immediately at planting, then chose blocks or specific trees to take to mature heights and open the other young black locust trees to the cattle to graze (as a supplemental forage for our infected fescue pastures in the summer).
Now the hard part, finding a viable seed source to start my project.
If anyone finds/hears of a source please let me know.
I believe Ernst Conservation Seeds, Meadville, PA has or can get you Black Locust seeds.
from "improved" trees?