From Common Forest Trees of Hawaii

Hōʻawa
Pittosporum confertiflorum
Cheesewoods family (Pittosporaceae)

Native species (); some introduced

This variable species is an example of its , which has about 10 Hawaiian species known as hō‘awa, also two species. Small shrubs or trees with large narrow leathery leaves on stout twigs, many small whitish flowers crowded at the base of leaves, and large rounded or four-angled deeply wrinkled that split open into two parts.


©2014 Forest And Kim Starr
To 30 ft (9 m) in height and 8 inches (0.2 m) in trunk diameter, with an open of few stout, stiff erect branches. Bark gray, smooth to fissured. Inner bark orange or light yellow with green outer layer, bitter. Twigs stout, gray, with pressed brown hairs when young, smoothish, with clustered large half-round leafscars and long portions without leaf-scars.

, many crowded near the end of erect twigs, with stout light yellow leaf-stalks of 3⁄8–2 inches (1–5 ). to , mostly 2 1⁄4–4 inches (6–10 ) long and 1–1 1⁄2 inches (2.5–4 ) wide, the largest to 8 inches (20 ) by 4 inches (10 ), thick, stiff, blunt at , widest beyond middle and gradually narrowed toward base, curved under at edges. Upper surface dull green, densely gray hairy when young, becoming nearly hairless, with sunken light yellow and network of prominently sunken veins; lower surface densely brown hairy, with raised veins.

Flower clusters (corymbose ) mostly at leaf bases, about 1 inch (2.5 ) long. Flowers many, fragrant, crowded on short brown hairy stalks, or male and female, about 3⁄8 inch (1 ) long, composed of cup-shaped five- brown hairy about 1⁄4 inch (6 ) long; white with cylindrical tube about 3⁄8 inch (10 ) long with five spreading 1⁄4 inch (6 ) long. Male flowers have 5 alternate attached at the base of the tube and extending beyond. Female flowers have five minute nonfunctioning and a narrow with hairy slightly two- , two-celled and containing many , and slender .

(seed ) usually single (sometimes 2–3), rounded or four-angled, 3⁄4–1 1⁄2 inches (2–4 ) long, brown, with point at , hard and thick-walled, the surface finely hairy, rough, deeply wrinkled, splitting into two parts, one-celled, inner wall orange, resinous or mucilaginous within. Seeds are many, elliptical, flat, more than 1⁄4 inch (6 ) long, shiny black.

The most widespread and common species of this in Hawaii, occurring from dryland forests to moist forests at 600–7200 ft (183–2194 m).

Special areas
Haleakala, Volcanoes

Range
Oahu, Lanai, Maui, and Hawaii only

Other common name
hā‘awa

Botanical
Pittosporum cauliflorum Mann, P. cladanthum Sherff, P. confertiflorum Gray, P. halophiloides Sherff, P. halophilum Rock, P. lanaiense St. John

Rock (1913) observed that the trees in this are very variable and that it is difficult to render the exact limitation of each species. He found of three different “species” on a single twig on the island of Lanai, where the is exceedingly well represented. As there are as many different forms as trees, one would be naming individual trees. Insect pollination is a factor, he concluded.

One native and a few introduced species are planted as ornamentals. In Hawaii, a home remedy was obtained from the pulp of the pounded . Plants of another native species, Pittosporum hosmeri Rock, can be seen on the grounds of the Bishop Museum.

stamen -- the pollen-producing reproductive organ of a flower; The stamen consists of an anther supported by a filament.

lobe -- Being divided by clefts.

cm -- A centimeter which is about 0.4 inches.

perfect flower -- a bisexual flower, having both male and female parts.

a non-native plant that has adapted to a new environment and continues to spread.

leaves alternate along the main stem and are attached singly.

style -- This is a long and thread-like structure that connects the stigma with the ovary. A flower may have a single style, or several of them.

midrib -- The central and most prominent vein of a leaf or leaf-like thing.

The apex is the tip or the furthest point from the attachment.

terminal -- Located at the end (the tip or the apex).

endemic -- when restricted to a certain country or area.

obovate -- Teardrop-shaped, stem attaches to tapering point.

ovules -- the part of the ovary of seed plants that contains the female germ cell. After fertilization an ovule becomes the seed.

A raceme is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along its axis.

A pistil is the female structure of many flowers. It contains one or more carpels. Each carpel contins an ovary, style and stigma. The stigma receives the pollen which grows thru the style to reach the ovary.

oblong -- Having an elongated form with somewhat parallel sides. Rectangular.

An evergreen tree retains a large portion of its green leaves all year.

lobe -- A rounded parts of a leaf (or other organ).

calyx -- the sepals of a flower, typically forming a whorl that encloses the petals and forms a protective layer around a flower in bud.

fruit -- any seed-bearing structure in flowering plants. It is formed from the ovary after flowering.

An ovary is a part of the female reproductive organ of the flower. Above the ovary is the style and the stigma, which is where the pollen lands and germinates to grow down through the style to the ovary.

synonym -- In botany a synonym is a species name that at one time was thought to be the correct name for a plant but was later found to be incorrect and has been replaced by a new name.

mm -- millimeter. About 1/25th of an inch.

corolla -- The name for all the petals of a flower taken together.

capsule -- a type of simple, dry fruit produced by many species of flowering plants. In most cases the capsule splits apart to release seeds.

canopy -- The foliage of a tree; the crown. Also the upper layer of a forest.

genus -- A subdivision of a botanical Family in which all members have a significant number of similar characteristics.

blade -- Just the flat part of a leaf. Not the stem.