Fagaceae

Figure 9.3 in your text showing the major eudicot clades.

Plant Sex: Flowers unisexual (plants monoecious).

Flowers: Very reduced, adapted to wind pollination. Perianth reduced or absent.

Inflorescence: Staminate inflorescence an AMENT (catkin). Carpellate inflorescence composed of three flowers subtended by a series of bracts called an INVOLUCRE. See Figure 9.86 for a diagram of the evolution of the involucre (cupule) in Fagaceae.

Fruits: Nuts, subtended by an involucre (the acorn cup in Quercus, the spiny husk in Castanea).

Habit: Deciduous and evergreen trees and shrubs.

Leaves: Simple, alternate, with stipules.

Examples:

Castanea (chestnut)

C. sativa. Habit of tree in flower from Kew Gardens. Staminate inflorescences. Carpellate inflorescences, one in L.S. Fruits. Fruits with nuts inside.
C. dentata. The American Chestnut that was devastated by chestnut blight.

Fagus (beech)

F. grandifolia. Habit of the tree. Staminate inflorescences. Carpellate inflorescence. Young infructescences. Infructescences dissected showing two flowers per involucre. Fruiting branch. Mature fruits.
F. sylvatica. The European beech. Fruiting shoot. Contorted trunk of tree in Spain.

Quercus (oaks)

Q. prinoides (Yellow chestnut oak; = Q. muhlenbergii). Branch with leaves and fruits (acorns). This is a member of section Lobatae (black and red oaks). Note the lobes are bristle-tipped. These acorns take two years to mature.
Q. stellata (Post oak). Branch with leaves and fruits (acorns). This species is a member of section Quercus (white oaks). The leaves are lobed but without bristle tips. The acorns mature in just one year.
Q. ellipsoidalis (Hill's oak). Staminate inflorescence. Close-up of staminate flowers, anthers not quite mature. Shoot showing staminate and carpellate flowers. Close-up of carpellate flowers. Mature acorns.
Q. rubra (Red oak). Carpellate flowers. Second year carpellate inflorescence with young acorns developing.
Q. palustris (Pin oak). Clustered terminal buds. Young leaf with axillary trichomes. Branch with staminate inflorescences. Shoots with previous year (left) and current year (right) carpellate flowers. Shoot with nearly mature acorns. Mature acorns.

Nothofagus (southern hemisphere beech) is now classified in its own family, Nothofagaceae

SIUC / College of Science / Elements of Plant Systematics
URL: http://www.plantbiology.siu.edu/PLB304/Lecture19Fagal/Fagaceae.html
Last updated: 01-Apr-09 / dln