I was poking around on the web and found this statement regarding propagation of Seguins.
Castanea seguinii is a deciduous Tree growing to 10 m (32ft 10in) at a medium rate.
It is hardy to zone (UK) 6. It is in flower in July, and the seeds ripen in October. The flowers are monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and are pollinated by insects.
USDA hardiness zone : 5-9
Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: acid and neutral soils and can grow in very acid soils.
It cannot grow in the shade. It prefers dry or moist soil and can tolerate drought.
Habitats
Woodland Garden Canopy
Propagation
Seed - where possible sow the seed as soon as it is ripe in a cold frame or in a seed bed outdoors[78]. The seed must be protected from mice and squirrels. The seed has a short viability and must not be allowed to become dry. It can be stored in a cool place, such as the salad compartment of a fridge, for a few months if it is kept moist, but check regularly for signs of germination. The seed should germinate in late winter or early spring. If sown in an outdoor seedbed, the plants can be left in situ for 1 - 2 years before planting them out in their permanent positions. If grown in pots, the plants can be put out into their permanent positions in the summer or autumn, making sure to give them some protection from the cold in their first winter.
Cultivation details
Prefers a good well-drained slightly acid loam but succeeds in dry soils[1, 11, 200]. Once established, it is very drought tolerant[1, 11, 200]. Very tolerant of highly acid, infertile dry sands[200]. Averse to calcareous soils but succeeds on harder limestones[11, 200]. This species can vary in size from a shrub 4 metres tall to, rarely, a tree 12 metres tall[266]. It is allied to the dwarf N. American species C. pumila[11], but unlike that species it has 3 seeds per bur[183]. Valued in breeding programmes because of its dwarf stature and heavy bearing at an early age[183]. Sometimes cultivated for its edible seed in China[266]. Although it is winter-hardy in most of Britain, this species only really thrives in areas with hot summers[200]. An excellent soil-enriching understorey in pine forests[200]. Flowers are produced on wood of the current year's growth[229]. Plants are fairly self-sterile[200]. They hybridize freely with other members of this genus[200]. Plants in this genus are notably resistant to honey fungus[200].