Achene
Related Category: Plants
(kn´), dry, simple, one-seeded fruit with the seed attached to the inner wall at only one point. Achenes are indehiscent, i.e., they do not split open at maturity.
Achene " A hard, one-seeded, indehiscent nutlet with a tight pericarp. An example is the sunflower seed in the shell (pericarp). Biseriate " Having two series, or rows, of parts; having two rows or sets of phyllaries (bracts) on the involucre.
achene: a dry 1-seeded indehiscent fruit; e.g. members of the Ranunculaceae.
acicular: slender or needle-shaped. See Leaf shape.
acropetal: moving from roots to leaves, e.g. of molecular signals in plants.
ACHENE
An achene is a dry, indehiscent one-seeded fruit with a leathery pericarp that is easily separated from the seed coat (for example, sunflower).
Achenes of prickly rose need both warm and cold stratification for germination.
Can be successfully started from rhizome, softwood, and hardwood cuttings. Cuttings that include both rhizome and stem tissue give the best results.
Cultivation: ...
Fruit: Achenes brown, obovoid (0.4 x 0.2 mm) surfaces finely reticulate (latticed).
Achene A one-seeded, dry, indehiscent fruit with the seed coat not attached to the mature ovary wall. Alternate In reference to leaves: occurring at different levels successively on opposite sides of stem. Annual Living only for one year.
Some botanists refer the genus Cineraria to the same order as the Senecio; these differ from Senecio in the achenes of the rayflorets being winged.
The strawberry "fruit" is actually a fleshy receptacle with many dry, thin walled achenes imbedded in its surface. Each achene (the true fruit) contains a single seed.
flammula, in which the flowers are without involucre or petals and the achenes or seed-like fruits are lengthened out into a bearded, feathery tail- represented by C. flammula.
C. viticella, in which the flowers are as in C.
The pistils are usually enclosed by a urn-shaped receptacle which develops into a orange or red berry-like fruit (hip) when ripe; it contains many achenes.
Fruit: A spherical multiple of achenes borne on a 3 to 6 inch stalk. Each seed is tiny, winged, and 1/2 inch long; maturing in November, disseminating in late winter.
Fruits: achenes, slender, 15-25 mm long, rather
abruptly narrowed to the slender, relatively short beak,
which is shorter than the achene. Pappus of whitish,
feathery bristles.
Distribution
Roadsides, fields and disturbed areas, commonly in ...
The fruit is an achene surrounded by a dark purple edible fleshy perianth, ripening in the fall. Young trees appear pyramidal until the multiple trunks begin spreading. This can form a rounded vase on older specimens.
The small, dry, single-seeded fruits of Canada thistle, called achenes, are 1-1½ inches long and have a feathery structure attached to the seed base. Many native species of thistle occur in the U.S., some of which are rare.
Flower-heads are inconspicuous at flowering, clustered near the base of plant and separated by short obscured internodes, 5-12 mm in diameter at fruiting, with 30-numerous mature achenes. Achenes are 3-4.5 x 1-1.
Each perigynium is subtended by an unfused bract referred to as a pistillate scale. If there are two stigmas or style branches, the achene is lenticular (two sided); if there are three stigmas or style branches, the achene is trigonous (three sided).
The feather-fruits (shown in the second photo) are called achenes. Though the flowers nod (as in the first photo), the stems turn upright by the time the fruit appears, so their feathery heads are a bit like troll-dolls with pink hair.
It is called "hooked" because of a hooked beak on each achene (the dry fruit around each seed). Hooked crowfoot is one of six species of buttercups in Connecticut with tiny flowers (Ranunculus abortivus, R. allegheniensis, R. micranthus, R.
In Asteraceae, the "pappus" is the modified calyx, made of hairs, bristles, or scales that are attached at the apex of the achene (the sunflower seed). In the Hymenopappus genus the pappus usually consists of short, membrane-like scales.
It matures as an achene (a dry seed) or a nutlet. The fruit is either lens-shaped or three-sided, the shape dependant on the number of carpels. Worldwide, there are about 90 genera and 4,000 species. Twenty-four genera are found in North America.
2" long hairy, oblong, and acute achenes in early summer.
Pathology:
There are few pest or disease problems with H. acutiloba.
Fruit: A thin achene with barbs (usually two) that can hang in fur and clothing.
Habitat: Fields and glades. Often in low areas or near water.
Range: Most of eastern and midwestern U. S. Except extream south.
Blooming Habits:
Dioecious. Minute whitish flowers in late summer, borne in attractive open panicles, followed, on the female plants by brown, shiny, triangular achenes, about 0.12 inch long (3 mm).
Fruiting Habits:
...
alternate leaf arrangement
pinnately compound leaves with 3 to 7 leaflets
yellow buttercup flowers June until frost
persistent achene ...
In medicinal purposes are used the fruit harvested in the months August - September, when the hips have turned dark red.The hips are, from a botanical point of view, false fruit, the real fruit being those small, hairy achenes inside.
A leafless flower stalks of this kind is known as a scape. This scape gets thicker beneath each flower head. The flowers are bright yellow. The achenes are cylindrical and have a single row of feathered hairs around one end.
Flower heads are up to three inches wide; the rounded central portion bears a hundred or more brown disc flowers, while from the periphery radiate about two dozen rose-purple ray flowers that are up to an inch long. Fruits are four-angled achenes ...
The flower-heads are 6 - 9 mm in diameter, and borne singly at the ends of the flower-stems. The heads have yellow rays ("petals"), 4.5 - 5.8 mm long. The seeds ("achenes") are 1.3 - 2.
FIG. 87. - Fruit of the Strawberry (Fragaria vesca), consisting of an enlarged succulent receptacle, bearing on its surface the small dry seed-like fruits (achenes).
No more details are given, but this report is somewhat suspect, the plant does not produce a fleshy fruit and the seed case certainly does not look edible[K]. The fruit is a dry, somewhat plump achene about 5mm in diameter[200].
The fruits are long, cylindrical, glabrous achenes, with shiny white down at the tip, appearing at the same time as the large leaves.
shrub or tree in its native haunts of Chile in the spring of 1998, and have come away with renewed admiration for it." It was last mentioned in the 2004 catalog, where Dan added that the flowers are followed by "pretty silky tufts of white achenes.
 See also: May, Green, Fruits, Aster, Medic
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