Word of the Week

Pyxis: A circumscissile capsule, the top coming off as a lid.* Above is an image of a ripe Portulaca pyxis. Circumscissile means that the capsule splits horizontally in a line …

Pseudanthium: A compact inflorescence of many small flowers which simulates a single flower.* While sunflowers look like one massive flower at the top of the stalk, they are actually composed …

Pappus: A modified calyx made up of a ring of fine hairs, scales, or teeth that persist after fertilization and aid the wind dispersal of the fruit, often by forming …

Gall: An abnormal growth or swelling in a plant. The formation of a gall may be induced by infection of the plant with bacteria or fungi, or by attack from …

Cupule: A cup-like sheath surrounding or enclosing certain fruits, e.g. the acorn of Quercus (Oaks).* The acorns on this English oak (Quercus robur) are maturing. The ‘caps’ at the top …

Pterocaulous: With winged stems.* Euonymus alatus, also known as winged euonymus or burning bush, is a common garden shrub from Asia that has become invasive in North America. It has …

Receptacle: In flowers and fruits, tissue to which all the floral whorls are attached.* A strawberry is not a berry at all. It is actually a swollen receptacle. Each of …

Sarmentose: Having long, thin runners (stolons).* Strawberries produce long runners, with new plantlets rooting along the ground. The image on the right shows the long runners producing plantlets. See also …