From Common Forest Trees of Hawaii

Melaleuca quinquenervia
Eucalyptus-Like family (Myrtaceae)

Post-Cook introduction

Paperbark, introduced for ornament and watershed cover, is easily recognized by its odd whitish bark, which splits and peels in many papery layers, by the lance-shaped or narrowly elliptical leaves with mostly five veins from base to and many white flowers with many threadlike crowded and stalkless, suggesting a bottlebrush. Crushed leaves have a resinous odor and taste somewhat like those of eucalyptus.

©2015 Zoya Akulova
An resinous ornamental and forest tree 20–50 ft (6–16 ) high, the trunk 1 ft (0.3 ) in diameter, slightly angled and grooved, with main axis and branches forming a narrow or open In age, a large tree to 75 ft (23 ) and 2–3 ft (0.6–0.9 ). Bark of trunk and branches whitish, very thick, corky or spongy, composed of many light pink fibrous papery layers. Inner bark is light brown, slightly sour. Twigs long and slender, often drooping, light brown and finely hairy when young, turning gray. End and side buds round to cylindrical, 1⁄8–1⁄4 inch (3–6 ) long, greenish brown, composed of many rounded overlapping

Leaves with finely hairy light green leaf-stalks of 1⁄8 inch (3 ). Blades 1 1⁄2–3 1⁄2 inches (4–9 ) long and 1⁄4–3⁄4 inch (6–19 ) wide, long-pointed at both ends, not on edges, slightly thickened and stiff, upper surface gray green and hairless, with five (sometimes seven) veins (as specific name indicates), faint and nearly parallel, lower surface paler and often slightly hairy.

Flower clusters (spikes) 1–3 inches (2.5–7.5 ) long and 1 1⁄2 inches (4 ) across, at end of twig, which elongates and forms new leaves beyond, composed of many crowded stalkless flowers 5⁄8 inch (15 ) long. Flowers have base () 1⁄16 inch (1.5 ) long; of five half-round less than 1.5 long; five concave whitish petals nearly 1⁄8 inch (3 ) long; and about 30 threadlike white nearly 5⁄8 inch (15 ) long, slightly united in five groups at base and failing together early; and composed of inferior 2–4-celled with many ovules, long threadlike white and brown dot

Seed capsules, many crowded and stalkless in groups 1–3 inches (2.5–7.5 ) long on gray twigs back of leaves or between groups of leaves, short cylindrical, 1⁄8 inch (3 ) long and 3⁄16 inch (5 ) wide, gray brown, hard and opening at flattened by 3–4 blunt hairy valves or teeth. Seeds are many, minute, less than 1⁄16 inch (1.5 ) long, very narrow, brown.

Sapwood is pale brown and heartwood light pinkish brown. Wood heavy ( gr. 0.58) with fine texture. Wood grown in Australia is reputed to be resistant to decay and termites, but these properties have not been evaluated for Hawaii-grown wood. Australian wood ( gr. 0.67) is quite strong in bending, tough, and hard, comparable to somewhat denser eucalypts in these properties. Tests of wood from Florida indicate that it is similar in properties to dogwood (Cornus ). The wood has not been used in Hawaii but should be suitable for fence posts. The problem with utilization is that the inside bark diameter of the stems is generally quite small.

A fast growing hardy tree resistant to wind, drought, fires, and salt water and suitable for windbreaks and beach planting. Propagated from seeds.

The thick papery bark has served elsewhere as packing material for caulking for boats, and as torches. Cajeput oil of medicine is obtained from the leaves and twigs of this and related species by steam distillation.

In Hawaii, the paperbark is grown extensively in pure and mixed forest stands for watershed cover, windbreaks, and as an ornamental. Naturalized, but not a pest as in Florida. Forest fires, which cause the seed pods to open and disseminate the seeds, are rare in Hawaii while common in Florida. The first recorded planting by the Division of Forestry was in 1917 on the land of Luaalaea in Manoa Valley, Oahu. Since then, the paperbark has become the third most commonly planted tree in Hawaii, with more than 1.7 million trees planted in the Forest Reserves, because it thrives on very harsh eroded and wet sites where others do not.

Special areas
Tantalus, Kalopa

Height 75 ft (22.9 ), c.b.h. 10.2 ft (3.1 ), spread 66 ft (20.1 ). State Forestry Arboretum, Hilo, Hawaii (1968).

Native from eastern Australia to New Caledonia and Papua, where it grows on coastal flats. Planted and naturalized in tropical regions. Naturalized and very common in southern Florida. Planted also in southern Texas, southern California, and Puerto Rico.

Other common names
paperbark-tree, bottlebrush, punk-tree; cayeputi, cayeput (Puerto Rico)

Formerly referred to as Melaleuca leucadendron (L) L, a related species of northern and northeastern Australia, southern New Guinea, and Amboina.

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

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

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.

scale -- A very small leaf around a dormant bud. Also other things that might remind one of fish scales on the surface of ferns, stems and the like.

cm -- A centimeter which is about 0.4 inches.

Irregular flowers, such as those of the violet or the pea, are often bilaterally symmeteric. These flowers typically have petals of unequal size or shape.

The hypanthium or floral cup is a cup-like structure formed by the fused bases of the stamens, petals, and sepals.

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

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.

alternate -- leaves alternate along the main stem and are attached singly.

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

m -- A meter is about 10% larger than a yard.

persistent -- When the leaves of a plant fail to fall off in the fall they are persistent. Flowers that stay around after fruiting would be persistent.

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

Like the teeth on a saw, leaves and other surfaces can have toothed edges.

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

lobe -- Rounded parts of a leaf (or other organ). Lobes bulge out about 1/4 of the leaf diameter.

stigma - The tip of a pistil that receives the pollen.

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

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.

sp. -- The abbreviation for "species". The plural is "spp". When used it sometimes means that the exact species is unknown. For example, "Aster sp" would mean some species within the Aster genus but the writer may not know exactly which species.