Deciduous or evergreen trees, occasionally shrubs. Leaves alternate (rarely whorled), simple, entire, toothed or lobed, occasionally pinnately lobed; stipules usually soon shed. Buds with overlapping scales. Flowers mostly unisexual with both sexes on the same plant, in catkins or small spikes, the sexes occasionally mixed on the same catkin as in Castanea. The pollen structure and strongly scented catkins suggest that the flowers were at one time insect pollinated, a condition now appearing to apply only to Castanea, the other genera being mostly wind pollinated. Male catkins with flowers solitary or along the stalk; perianth with 4-7 scaly lobes occasionally fused at the base; stamens up to 40 but generally the same number as or double that of the perianth lobes; filaments free. Female flowers 1-3 together and with a basal bract, sometimes at the base of the male catkins. Carpels fused. Ovary inferior with 3-6 styles and mostly 3 chambers each containing 2 ovules. Fruit of nuts grouped 1-3 in a cup-like structure of various forms.
This family dominates the northern hemisphere broadleaf deciduous and mixed forests and is generally considered most closely related to the Betulaceae. The ancient southern beeches (Nothofagus) of the southern hemisphere have a distribution and fossil history indicating a Gondwanan origin, and although they have sometimes been included in Fagaceae in the past, they are now placed in their own family, Nothofagaceae.
The genera Lithocarpus (closely related to the oaks) and Castanopsis (closely related to the sweet chestnuts) are occasionally represented in specialist collections.
Economically the family is a valuable source of hardwood timber which has a wide range of uses. Commercial cork is the bark of the Cork Oak, Q. suber, and oak galls are the source of tannins. The nuts are often used as food for stock and those of the chestnut are edible and the source of commercial compounds.
Trees with simple leaves; flowers in catkins; ovary inferior.
A widespread family of 8 genera and about 800 species mostly of temperate and tropical forests; found in all regions except tropical and southern Africa.
Source: (1997). Fagaceae. In: . Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.
Updated by: Rob Cross, December 2017