fagaceae
Monoecious trees or shrubs. Leaves simple, alternate, entire or lobed, cleft or parted, veins straight, stipules caducous. Staminate flowers in axillary catkins or in globose heads; pistillate flowers solitary or in small clusters on short spikes; styles 3. Fruit a nut enclosed or partly enclosed by an involucre or cup of wholly or partly fused, hardened bracts.
Involucre covering the nut
FAGUS
(see Fagus grandifolia)
CASTANEA
Trees or shrubs. Leaves deciduous, pinnately veined, coarsely toothed, the teeth usually bristle-tipped. Staminate flowers clustered in slender catkins, some of the short catkins bearing pistillate flowers near the base, some bearing only pistillate flowers; pistillate flowers 2-9 per involucre. Nuts brown, surrounded by prickly involucre that splits into 2-4 valves at maturity.
QUERCUS
Monoecious trees or shrubs. Leaves deciduous or evergreen, often lobed, cleft or parted, the margins serrate, crenate or entire, the lobes or teeth with or without bristles. Staminate flowers in clustered, drooping catkins, each flower with a 2-8 lobed calyx, and 3-12 stamens; pistillate flowers solitary or 2 or more on a short spike, calyx 6-lobed. Stigmas 3, ovary usually 3-locular, each flower surrounded by an involucre of many scales that at maturity harden into a cup around the base of the nut or acorn, or in some species may nearly cover the nut. Some species produce acorns in the first year, some mature fruit in the fall of the second year.
IDENTIFICATION KEY
Involucre covering the nut
- Involucre with recurved single spines; mature buds more than 1 cm long, slender.......................Fagus
- Involucre with straight clustered spines; mature buds less than 1 cm long, not slender...............Castanea
- Involcre forming a cup, not covering the nut.....................................................................................Quercus
FAGUS
(see Fagus grandifolia)
CASTANEA
Trees or shrubs. Leaves deciduous, pinnately veined, coarsely toothed, the teeth usually bristle-tipped. Staminate flowers clustered in slender catkins, some of the short catkins bearing pistillate flowers near the base, some bearing only pistillate flowers; pistillate flowers 2-9 per involucre. Nuts brown, surrounded by prickly involucre that splits into 2-4 valves at maturity.
QUERCUS
Monoecious trees or shrubs. Leaves deciduous or evergreen, often lobed, cleft or parted, the margins serrate, crenate or entire, the lobes or teeth with or without bristles. Staminate flowers in clustered, drooping catkins, each flower with a 2-8 lobed calyx, and 3-12 stamens; pistillate flowers solitary or 2 or more on a short spike, calyx 6-lobed. Stigmas 3, ovary usually 3-locular, each flower surrounded by an involucre of many scales that at maturity harden into a cup around the base of the nut or acorn, or in some species may nearly cover the nut. Some species produce acorns in the first year, some mature fruit in the fall of the second year.
IDENTIFICATION KEY