bract

Toothed bracts on Rhinanthus minor

In botany, a bract is a modified or specialized leaf, from the axil of which a flower or flower stalk arises. A bract may also be any leaf associated with an inflorescence. Usually bracts are green and resemble the other leaves. Some bracts, however, are brightly colored and serve the function of attracting pollinators, either in concert with or instead of the tepals. An excellent example of this latter type of bract occurs in the Poinsettia plant (Euphorbia pulcherrima).

A small bract is called bracteole or bractlet. Technically it is any bract that arises on a pedicel instead of subtending it. In grasses, the bracts that enclose the florets are termed glumes.

Bracts that appear in a whorl are collectively called an involucre. An involucre is a common feature under the inflorescences of many umbelliferous and asteraceous plants. Each flower in an inflorescence may have its own whorl of bracts, in this case called an involucel. Many asteraceous plants have bracts both at the flower base and inflorescence base. Those at the flower base — chaff (recepticular bracts) — are usually minute. Those at the base of the inflorescence or head — the involucral bracts — are usually green, narrow, and leafy. A phyllary is another term for one of the scale-like bracts beneath the flowerhead in Asteraceae species.

A prophyll is a leaf-like structure, such as a bracteole, subtending a single flower or pedicel. The term can also mean the lower bract on a peduncle.

A spathe is a large bract that forms a sheath to enclose the flower cluster of certain plants such as palms and arums. In many arums, the spathe is petal-like, attracting pollinators to the flowers arranged on a type of spike called a spadix.

The frequently showy pair of bracts of cyathia of Euphorbia species in subgenus Lacanthis is termed cyathophylls.

Gallery

Bracts on Leafy-bract Beggar-tick (Bidens comosa)	Bracts surrounding a banana flower stalk	In Bougainvillea each cluster of three flowers is surrounded by three or six more colorful bracts	Bright red bracts of Euphorbia pulcherrima (Poinsettia)
Yellow petal-like bracts of Euphorbia epithymoides	Euphorbia milii var. vulcanii cyathia bearing a pair of pinkish cyathophylls	Green bracts surrounding a sunflower bud	Showy white bracts of the Kousa Dogwood Cornus kousa
Large pink bracts of an Anthurium	Colourful bracts of Ananas bracteatus

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