Acorn - online puzzles

The acorn, or oak nut, is the nut of the oaks and their close relatives (genera Quercus and Lithocarpus, in the family Fagaceae). It usually contains a single seed (occasionally two seeds), enclosed in a tough, leathery shell, and borne in a cup -shaped cupule. Acorns are 1–6 cm (0.39–2.36 in) long and 0.8–4 cm (0.31–1.57 in) broad. Acorns take between 6 and 24 months (depending on the species) to mature; see the list of Quercus species for details of oak classification, in which acorn morphology and phenology are important factors.