It seems to me there is a step missing: plant seeds further north, some plants survive better than others even reproduce, take those survivors and repeat further north.
So not the fruit from all trees but from the ones that are better adapted. This could happen naturally but probably more slowly and also would naturally have to compete with local species.
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It seems to me there is a step missing: plant seeds further north, some plants survive better than others even reproduce, take those survivors and repeat further north.
So not the fruit from all trees but from the ones that are better adapted. This could happen naturally but probably more slowly and also would naturally have to compete with local species.
This is the epigenetic vs plain genetic part.
I read more in this a while back, and they also dug special ditches, did some orher things, to make the environment more friendly.