panicled ticktrefoil (EwA Guide to the Plants of the Fells (US))

panicled ticktrefoil

Desmodium paniculatum

Summary ⁷

Desmodium paniculatum, called panicledleaf ticktrefoil, narrow-leaf tick-trefoil, and panicled tickclover, is a perennial herb and wildflower in the pea family native to eastern and southern North America.

Description ⁸

This native perennial wildflower is 23½' tall, sometimes branching in the upper half. The stems are light green and usually hairless; however, some variants of this species have pubescent stems. Alternate compound leaves occur at intervals along the stems; they are trifoliate and their leaflets are extended horizontally in relation to the ground. Individual leaflets are up to 3½" long and ¾" across; they are 3-6 times as long as they are wide. Some variants of this species have more narrow leaflets than others. The terminal leaflet is the same length or a little longer than the lateral leaflets. The leaflets are elliptic to oblong in shape and smooth along their margins. Their upper surfaces are medium green and glabrous, while their lower surfaces are pale to medium green and covered with appressed white hairs. The petioles of the compound leaves are up to 2" long, light green, and mostly hairless. At the base of each petiole, there is a pair of tiny deciduous stipules that are linear-lanceolate; these stipules soon wither away. The petiolules (secondary petioles) of the lateral leaflets are very short (1/8" or less), while the petiolules of the terminal leaflets are longer (up to ½"). The upper stems terminate in either racemes or narrow panicles of flowers. The branches of each inflorescence are light green and covered with hooked hairs. Individual flowers are ¼" long (or a little more), consisting of 5 petals, a short tubular calyx with teeth, an ovary with a single style, and several hidden stamens. The flowers have a typical pea-like structure, consisting of an upright banner and 2 lateral wings that enclose a central keel. The petals are pink to rosy pink; at the base of the upper petal (banner), there are 1-2 tiny patches of yellow. The green calyx is covered with hooked hairs. The slender petioles of the flowers are about ½" long; they are green to reddish purple and also covered with hooked hairs. The blooming period occurs from mid-summer to early fall and lasts about 11½ months. There is no noticeable floral scent. Fertile flowers are replaced by flat loments (a type of seedpod) that are about ½1½" long. Each loment consists of 2-6 rounded segments, a short stipe, and sometimes a short beak. Each segment of a loment is more rounded along the bottom than along the top; it contains a single seed. The loments are covered with hooked hairs. The root system consists of an elongated caudex with fibrous roots. This wildflower spreads by reseeding itself.

Sources and Credits

(c) Gravitywave, some rights reserved (CC BY-NC-SA), http://www.flickr.com/photos/74215305@N00/1461504506
(c) anonymous, some rights reserved (CC BY-NC), http://www.illinoiswildflowers.info/savanna/photos/pn_tktrefoil1.jpg
(c) Cooper, G.A., some rights reserved (CC BY-NC-SA), https://collections.nmnh.si.edu/services/media.php?env=botany&irn=10327973
(c) anonymous, some rights reserved (CC BY-NC), http://www.illinoiswildflowers.info/savanna/photos/pn_tktrefoil2.jpg
(c) Erin Faulkner, some rights reserved (CC BY-NC), uploaded by Erin Faulkner
(c) anonymous, some rights reserved (CC BY-NC-SA), https://collections.nmnh.si.edu/services/media.php?env=botany&irn=10286959
(c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Desmodium_paniculatum
(c) John Hilty, some rights reserved (CC BY-NC), http://eol.org/data_objects/29443285

More Info

Range Map

iNat Map

Flowering season	summer
Flower color	pink

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