Chestnut which are mildly poisonous to humans. Nor should they be confused with water chestnut, which are tubers of an aquatic herbaceous plant in the sedge family Cyperaceae. Other trees commonly mistaken for chestnut trees are the chestnut oak ("Quercus prinus") and the American beech ("Fagus grandifolia"), both of which are also in the Fagaceae. The name "chestnut" is derived from an earlier English term "chesten nut", which descends from the Old French word "chastain" (Modern French, "châtaigne"). The French word in turn derives from Latin "Castanea" (also the scientific name of the tree), which traces to the Ancient Greek word
Fagus sylvatica in the buds. In autumn, the tree builds the reserves that will sustain it into spring. Given good conditions, a bud can produce a shoot with up to ten or more leaves. The terminal bud emits a hormonal substance in the spring that halts the development of additional buds. This tendency, though very strong at the beginning of their existence, becomes weaker in older trees. It is only after the budding that root growth of the year begins. The first roots to appear are very thin (with a diameter of less than 0.5 mm). Later, after a wave of above