Most modern varieties of Chestnut, just like most fruit trees, need to be grafted onto a vigorous root stock. A few very productive old fashioned varieties, however, can be cultivated from young shoots (I'm afraid I don't know the names of these).
This is how the clever little devils go about the process over here, which, in all, has taken 3 years (so far).
Having chopped down a dying tree, it will sprout small branches from around the base of the severed trunk, when these are large enough (i.e. the following year), a solid piece of wire is twisted very tightly just above where it joins the trunk; in effect strangling it, and forcing it to grow it's own roots just beyond the wire noose, underneath a good deep covering of soil.
The following year (i.e. year 3), the soil is removed revealing each small branch complete with its own bunch of healthy roots. The branches are then cut, the wire removed, and they are planted out.
I like this process. Time seems irrelevant, and you end-up with free Chestnut trees; whilst (more importantly) saving ancient varieties.
As with the planting of most trees, one plants for one's grandchildren. The only question nowadays being 'will those grandchildren have stayed on the farm, in order to appreciate the expediency of their forebears?'
I do hope so.