Flora of the Hawaiian Islands
Dicotyledon Literature for Verbena litoralis
Wagner et al., 1990, 1999.
   Verbenaceae -- The Verbena Family Bibliography
      Verbena litoralis

Common name(s): vervain, ha`uoi (Ni`ihau), ha`uowi (Ni`ihau), oi, owi
General Information
DistributionNative from Mexico through Central America to South America, widely naturalized.In the Hawaiian Islands, naturalized on Midway, Ni`ihau, Kaua`i, O`ahu, Moloka`i, Lana`i, Maui, Kaho`olawe, Hawai`i.

Erect or ascending perennial herbs 4-20 dm tall, sometimes somewhat woody toward base; stems few to many-branched, glabrous or sparsely strigillose.
Leaves decussate, lanceolate to oblanceolate, 3-10 cm long, 1-1.5 cm wide, both surfaces finely scaberulous, margins coarsely serrate, apex acute, base attenuate.
Flowers numerous in several slender, terminal spikes 3-12 cm long, sparsely short-pilose throughout, bracts subulate, shorter than to as long as the calyx; calyx sometimes purple, 1.5-2.3 mm long, short-pilose; corolla usually blue, occasionally pale blue, lavender, or purple, ca. 2-3 mm long.
2n = 28, 56