Flora of the Hawaiian Islands
Dicotyledon Literature for Vachellia farnesiana
Wagner et al., 1990, 1999; Lorence & Wagner, 2020.
   Fabaceae -- The Pea Family Bibliography
      Vachellia farnesiana

Common name(s): aroma, klu, kolu
General Information
DistributionNative to the Neotropics.In the Hawaiian Islands, naturalized on Midway, Kaua`i, O`ahu, Moloka`i, Lana`i, Maui, Kaho`olawe, Hawai`i.

Spiny shrub or sometimes a small tree to 4 m tall, bark rough, light brown; branchlets zigzaging, subglabrous.
Leaves, bipinnately compound, 2.7‒8 cm long, 2‒6 cm wide, (1)2‒8 pairs of pinnae, short-petiolate; leaflets 8‒25 pairs, 3‒7 mm long, 0.8‒1.5 mm wide, 1‒2 nectaries on the main rachis below the lowermost pair of pinnae; petiole 0.7‒1.8 cm long; stipular spines 0.4‒4 cm long.
Inflorescences a head to ca. 15 mm in diameter (excluding stamens), these solitary or few together on a short axillary axis, peduncle slender, 2‒4.5 cm long. Flowers bright yellow and fragrant when fresh, ca. 1.5 mm long; calyx glabrous; corolla glabrous; stamens ca. 2 mm long.
Fruit thick, subterete, straight or curved, 5‒7 cm long, 1‒2 cm in diameter, dark brown, indehiscent; seeds embedded in dry spongy tissue.
Seeds ellipsoid, slightly laterally flattened, 7‒8 mm long, 5‒5.5 mm in diameter; areole 6.5–7 mm long, 4 mm wide.
2n = 52, 104.
Planted throughout the world for its fragrant flowers, often becoming naturalized and considered a weed.
David Lorence