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I haven't tried it yet, but if Gendustry tree breeding works the same as it does with bees it would provide you with a pure sapling, thus meeting the NBT requirements.
Personally, I would love to see the mod list on the main page be a comparison table. All the mods listed down the left side, all the mod packs across the top, and a simple mark on the table to show if the mod is in that pack.