Flora of the Hawaiian Islands
Dicotyledon Literature for Hibiscus tiliaceus
Brown, 1935; Florence, 2004; Smith, 1979; Lorence & Wagner, 2020.
   Malvaceae -- The Cacao, Linden, Mallow Family Bibliography
      Hibiscus tiliaceus

Common name(s): aloalo, hau
General Information
DistributionA polymorphic species widespread in the tropics and subtropics worldwide, especially along coasts and river banks.In the Hawaiian Islands, indigenous to Midway, French Frigate Shoals, Ni`ihau, Kaua`i, O`ahu, Moloka`i, Lana`i, Maui, Hawai`i.

Shrub or small tree, 2‒10(‒20) m tall, habit often sprawling or tangled; young branches, petioles, and pedicels glabrous or finely stellate pubescent.
Leaves petiolate; blade coriaceous, cordate-ovate to cordate-orbicular, 8‒20(‒30) cm long, 8‒20(‒25) cm wide, unlobed, median vein or 3 central veins on abaxial surface with an elongate bordered gland near base, adaxial surface green, glossy, and subglabrous, abaxial surface closely white tomentose, margin entire or serrulate, apex abruptly acuminate, base cordate; petiole usually ¼‒¾ as long as blade; stipules foliaceous, 10‒60 mm long, enclosing the buds, clasping the stem in pairs, then deciduous leaving an annular scar.
Inflorescences terminal in few-flowered naked or leafy cymes, rarely a solitary flower, peduncle and pedicels articulate; involucral bracts connate basally to form a 7‒12-toothed cup usually ½ or less the length of the calyx, closely and smoothly stellate pubescent. Flowers with calyx 1.5‒3 cm long, lobed to middle and beyond, midrib of each lobe with a flat, elongate gland; corolla when fresh yellow, rarely whitish, usually brownish red to maroon at base, fading during the day through orange-yellow to dark red, drying greenish, convolute, basically tubular below with petals spreading above, 4‒7(‒8.5) cm long, broadly obtuse-rounded; staminal column included, closely antheriferous for most of its length; style branches erect, maroon, stigmas expanded and slightly decurrent.
Fruit oblong-ovoid, short beaked, 1.3‒2.8 cm long, valves firm, moderately woody, closely yellowish stellate pubescent.
Seeds reddish brown, reniform, to 4.5 mm long, striate with minute papillae or stellate tufts.
2n = 80, 92, 96.
We choose not to recognize infraspecific taxa in this widespread and variable species. Hibiscus tiliaceus ‘Sterilis’ is a cultivar grown in the Marquesas and Society Islands from near sea level to about 500 m as an ornamental, for its wood, and bark used for cordage. It is recognized by its erect trunk and branches, comparatively small leaves, juvenile leaves with crenate margin, and scarcity or absence of flowers or fruit. An ornamental form of H. tiliaceus with variegated green, pink-red, and white leaves has become popular in cultivation on some of the islands.
David Lorence