cutleaf evening primrose (Nash Prairie Plants List)

cutleaf evening primrose

Oenothera laciniata

Summary ³

Oenothera laciniata is a species of flowering plant in the evening primrose family known by the common name cutleaf evening primrose. It is native to the eastern United States but it can be found in many other places as an introduced species and sometimes a noxious weed. It is reported from Hawaii, Australia, Britain, France, Korea, Japan, and other areas. This is an annual or short-lived perennial herb producing a spreading stem from a hairy rosette...

Comments ⁴

Because the flowers usually bloom at night, Ragged Evening Primrose is a fairly low and inconspicuous plant. These flowers are very similar in appearance to those of Oenothera biennis (Common Evening Primrose) and other species in this genus. It is primarily the pinnatifid shape of the leaves that sets Ragged Evening Primrose apart; they have conspicuous lateral lobes. The leaf-margins of other Oenothera spp. in Illinois are usually less wavy. Another common name of Oenothera laciniata is Cutleaf Evening Primrose.

Description ⁵

Ragged Evening Primrose is a native annual about ½2' long; this plant often sprawls across the ground, or it is weakly ascending (particularly near the tips of its branches). Small plants are usually unbranched, while larger plants produce lateral stems occasionally. Each stem is terete, light green, and more or less hairy. Along each stem, there are alternate leaves up to 4" long and 1" across. The leaves are oblong-lanceolate to oblong-oblanceolate and pinnatifid; they are hairy, although less so along their upper surfaces. The middle to upper leaves are sessile, while the lower leaves have short petioles. From the axils of the middle to upper leaves, there develops individual flowers that are sessile. Each flower spans about 1" across when it is fully open, consisting of 4 yellow petals, a narrowly cylindrical calyx (about 2" long) with 4 narrowly triangular lobe-segments at its apex, a narrowly cylindrical ovary/fruit (about 11½" long), 8 stamens, and a central united style with cross-shaped stigmata. The flowers bloom at night and become closed during the morning. Even though it appears that each flower has a stalk-like pedicel about 3" long, this is actually the narrowly cylindrical calyx and ovary/fruit of the flower. The lobe-segments of the calyx hang downward. The blooming period occurs from late spring to mid-summer and lasts about 1½2 months. Only a few flowers are in bloom at the same time. After pollination of a flower, the entire calyx becomes pale salmon pink and falls off the fruit. The cylindrical fruit (or developing seed capsule) is straight to slightly curved and ascends upward; it is terete, slightly 4-ribbed, and more or less pubescent along its length. This plant reproduces by reseeding itself; the surfaces of the small seeds are pitted.

Sources and Credits

(c) Kathy McAleese, some rights reserved (CC BY-NC-ND), uploaded by Kathy McAleese
(c) Kevin Thiele, some rights reserved (CC BY), https://www.flickr.com/photos/66951228@N07/6280611830/
Adapted by Amber Leung from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Oenothera_laciniata
(c) John Hilty, some rights reserved (CC BY-NC), http://eol.org/data_objects/29442332
(c) John Hilty, some rights reserved (CC BY-NC), http://eol.org/data_objects/29442327

More Info

iNat Map

Family	Onagraceae
Blooms	April

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