From Common Forest Trees of Hawaii

Gunpowder Tree
Trema orientalis
Hemp/Hops/Hackberries family (Cannabaceae)

Post-Cook introduction

Medium-sized introduced weedy tree, recognized by the narrowly unequal-sided very long-pointed leaves with finely edges and three main veins from base, spreading in two rows on long slender twigs. To 60 ft (18 ) high and 2 ft (0.6 ) in trunk diameter. Bark light gray grown, smoothish, finely fissured. Inner bark is pink, soft and fibrous, bitter. Twigs long, slender, unbranched, spreading, light green, finely hairy, turning brown.


©2012 Forest And Kim Starr
Leaves borne singly () in two rows with slender leaf-stalks 3⁄8–3⁄4 inch (1–2 ) long, finely hairy. Blades narrowly 2 1⁄2–4 inches (6–10 ) long and 3⁄4–1 1⁄4 inch (2–3 ), wide, very long-pointed at base slightly notched with sides unequal, edges finely thin, with three main veins from base. Upper surface light green, slightly shiny, slightly rough, with veins sunken, lower surface dull and paler, soft hairy, with prominent light yellow veins.

Flower clusters () at leaf bases, branched, 3⁄8–2 inches (1–5 ) long and broad. Flowers are many, nearly stalkless, light green, 1⁄8 inch (3 ) long, male and female. Female flowers are composed of 5 tiny and with a one-celled and two whitish hairy spreading

() round, nearly 3⁄16 inch (5 ) in diameter, pink to black, fleshy. Seed single, round, brown, more than 1⁄16 inch (1.5 ) long.

Wood pale brown or buff, sapwood not distinct from heartwood. It is lightweight ( gr. 0.40), easy to work, and not resistant to decay or termites (Reyes 1938). The wood has not been used in Hawaii. It is said to make good charcoal for gunpowder, thus the common name.

A weed tree of rapid growth, extending into forest openings in moist lowland areas in Hawaii. It is particularly common in the vicinity of Hilo airport.

Champion
Height 72 ft (21.9 ), c.b.h. 20.5 ft (6.2 ), spread 108 ft (32.9 ). Pepeekeo, Hawaii (1968).

Range
Native from southeastern Asia through Malaysia

Other common names
charcoal tree; banahl (N. Marianas); elodechoel (Palau)

Trema cannabina Lour. (T. amboinensis (Willd.) Blume) is a related native species, a small tree to 30 ft (9 ) high with smaller hairy black about 1⁄8 inch (3 ) long, only slightly fleshy. Elsewhere, a fiber for fish nets has been made from the bark and medicine from other parts. In Hawaii, uncommon in lowland areas, recorded from the five largest islands. Native and more common in other Pacific Islands, such as Samoa, Fiji, and Tahiti, and southeastern Asia to China and India.

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.

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.

cm -- A centimeter which is about 0.4 inches.

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

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

ovate -- Oval, egg-shaped, with a tapering point.

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

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.

Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom.

cyme -- Multiple flower stalks emerge from a single point and the flowers at the end bloom first.

drupe -- A fruit in which an outer fleshy part surrounds a hardened shell containing a seed. A peach is a drupe. A raspberry is composed of drupelets.

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.

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.