1. Erodium cicutarium (L.) L’Hér. ex Aiton
(filaree, alfilaria, pink needle, pin clover)
Pl. 422 a–d; Map
1881
Plants
moderately to densely pubescent with more or less spreading, minutely
gland-tipped hairs. Stems 2–35 cm long, sometimes beginning to produce flowers
when very short, but elongating and somewhat mat-forming later in the season.
Leaves short- to long-petiolate. Leaf blades 2–10 cm long, narrowly
oblong-oblanceolate in outline, pinnately compound with 4–8 pairs of opposite
leaflets, these 4–13 mm long, mostly ovate to oblong-elliptic in outline,
deeply pinnately lobed, the lobes toothed or shallowly lobed along the margins.
Sepals 2.5–4.0 mm long at flowering, persistent and becoming elongated to 6.5
mm at fruiting, lanceolate to oblong-ovate. Petals 3–6 mm long, obovate,
narrowed to a stalklike base, pink to lilac, lavender or pale purple. Stamens
with the filaments gradually broadened toward the base. Mericarps 25–45 mm long
at maturity, the seed-containing basal portion 3.5–4.5 mm long, moderately to
densely pubescent with short stiff ascending hairs, the stylar beak with
inconspicuous short appressed hairs. Seeds 2–3 mm long. 2n=40 (2n=20,
36, 48, 54 in some European populations). March–November.
Introduced,
uncommon and sporadic, mostly south of the Missouri River (native of Europe,
Asia, Africa; widely introduced in most temperate regions of the world,
including the U.S. [including Alaska, Hawaii], Canada, Greenland, Mexico,
etc.). Glades, also lawns, roadsides, and open disturbed areas.
Filaree is a
widespread but mostly innocuous weed, although in the southwestern United
States, it can interfere with seedling establishment of crop plants in
cultivated fields. The petals are shed the same day that the flower opens.