Salicaceae

Plant Sex: Flowers unisexual (plants dioecious).

Flowers: Very reduced, adapted to wind or insect pollination. Perianth represented by a nectary (Salix) or scaly cup (Populus). Flowers often subtended by a bract. Placentation parietal.

Inflorescence: Flowers in AMENTS (catkins).

Fruits: Capsules with comose seeds (hairy, wind dispersed).

Habit: Trees and shrubs, some dwarfed (arctic). Salicin (salicylic acid, aspirin) from Salix.

Leaves: Alternate, simple, stipulate.

Examples:

Salix (willow)

S. babylonica (weeping willow). Staminate inflorescence (left), carpellate inflorescence (right).
S. discolor (pussy willow). Staminate inflorescences.
S. interior. Staminate (left) and carpellate inflorescence (right). Close-up of these. Staminate and carpellate flowers.
S. nigra. Branch with infructescences.

Populus (poplar, cottonwood)

P. alba. Habit of tree.
P. deltoides. Habit of the cottonwood tree. Fruits.
P. tremuloides (quaking aspen). Carpellate catkins (aments). Detail of staminate inflorescence. Photo showing simultaneous senescence of leaves in aspen genets derived from the same clone.

Why is the Salicaceae not related to other ament-bearing plants? Advanced features include:

Flowers simple by reduction
Wood anatomy
Parietal placentation
Salicin and populin (not found elsewhere)

SIUC / College of Science / Elements of Plant Systematics
URL: http://www.plantbiology.siu.edu/PLB304/Lecture16Malpig/Salicaceae.html
Last updated: 27-Feb-08 / dln