Les quenouilles (Typha latifolia) et de cardère (Dipsacus fullonum) les plantes à l'automne brise matinale. Image montrant la dispersion des graines dans le vent.
3420 x 5109 px | 29 x 43,3 cm | 11,4 x 17 inches | 300dpi
Date de la prise de vue:
8 novembre 2009
Lieu:
Aurora Colorado US.
Informations supplémentaires:
In the fall, Cattail head stalks (Typha latifolia) release hundreds of seeds when the wind blows. Cattails grow mostly in large, dense patches, and are found along borders of standing water and ditches in the plains states. The kind of seeds which are often wind dispersed are smaller seeds that have wings or other hair-like or feather-like structures, such as found from a Cattail. Plants that produce wind blown seeds, often produce many seeds to ensure that some of them are blown to areas where the seeds will germinate. Cattails are known to clean up poor water quality. Teasel- Dipsacus is a genus of flowering plant in the family Dipsacaceae. The members of this genus are known as teasel or teazel or teazle. The genus includes about 15 species of tall herbaceous biennial plants (rarely short-lived perennial plants) growing to 1-2.5 m tall, native to Europe, Asia and northern Africa. The genus name is derived from the word for thirst and refers to the cup-like formation made where sessile leaves merge at the stem. Rain water can collect in this receptacle; this may perform the function of preventing sap-sucking insects such as aphids from climbing the stem. The leaf shape is lanceolate, 20-40 cm long and 3-6 cm broad, with a row of small spines on the underside of the midrib. Teasels are easily identified with their prickly stem and leaves, and the inflorescence of purple, dark pink or lavender flowers that form a head on the end of the stem(s). The first flowers begin opening in a belt around the middle of the spherical or oval flowerhead, and then open sequentially toward the top and bottom, forming two narrow belts as the flowering progresses. The dried head persists afterwards, with the small (4-6 mm) seeds maturing in mid autumn. The seeds are an important winter food resource for some birds. Teasel is also considered an invasive species in the United States.- Wikipedia