Tough, resistant greenheart timber is a marine and shipbuilders' favorite.Among the many timbers suitable for marine construction and shipbuilding, greenheart green·heart n. 1. a. A tropical American tree (Ocotea rodioei) having dark, greenish, durable wood. b. Any of various similar trees. 2. The wood of any of these trees. (green*heart) earns very high marks. Its heartwood heartwood, the central, woody core of a tree, no longer serving for the conduction of water and dissolved minerals; heartwood is usually denser and darker in color than the outer sapwood. is highly resistant to attack by fungi, marine borers and dry-wood termites, and that makes the wood popular for marine and ship construction. In ships, the wood is used for everything from planking and gangways to engine bearers, stern posts, fenders, and sheathing. Greenheart (Ocotea rodiaei) is also used in docks, piling, revetments, lock gates, handrails and jetties, wharves Structures erected on the margin of Navigable Waters where vessels can stop to load and unload cargo. Cities located on lakes, rivers, and oceans usually have at least one wharf, where ships can deliver and pick up passengers and load and unload various types of goods. , canal locks, marinas and breakwaters. It is also used for mine work and decking of all kinds. The Illustrated Encyclopedia of Trees, Timbers and Forests of the World, by Herbert Edlin and Maurice Nimmo, offers information on why greenheart is so highly rated for these uses. "In the sea there are several animals that burrow into and live in wood under the water; the commonest of these are the teredo teredo: see shipworm. , or shipworm shipworm or teredo (tĕrē`dō), marine bivalve mollusk of the family Teredinidae, specialized for boring in wood. A shipworm is not a worm, but a greatly elongated clam. , and the gribble grib·ble n. Any of several small wood-boring marine isopod crustaceans of the genus Limnoria, especially L. lignorum, which often damage underwater wooden structures. ," Edlin and Nimmo say. They write that some trees, including greenheart, produce wood that is naturally fairly resistant to the animals. Albert Constantine Jr., in Know Your Woods, says greenheart rates a "close second to teak in resisting the white ant. Occasionally worms may attack the sapwood sapwood, relatively thin, youngest, outer part of the woody stem of a tree, the part that conducts water and dissolved materials. In the cross section of a tree, the sapwood is recognizable by its texture and color; it is softer and lighter than the inner heartwood. , but they do not penetrate into the heartwood." A Popular Export Greenheart is one of the most popular woods exported from Guyana. It also grows in Surinam, Venezuelan Guiana, French Guiana and northern Brazil. The wood's exceptional density and strength, with high bending and crushing strengths, makes it ideal for heavy work. It is suitable for bridge work and commercial flooring. Greenheart is also used for commercial flooring, filter press plates and turnery, and has very unique uses. The wood is used to make fishing rods, billiard bil·liard adj. Of, relating to, or used in billiards. n. See carom. Adj. 1. billiard - of or relating to billiards; "a billiard ball"; "a billiard cue"; "a billiard table" cue butts and longbows. Varied Colors Greenheart's heartwood varies in color. It ranges from yellowish green to light olive to dark green, and orange green to orange brown to dark brown. Sometimes it has black streaks. The variation in color leads to a long list of names based on the hue of the heartwood, such as black greenheart, yellow greenheart, brown or white. The sapwood is usually a pale, yellowish green. The color is not supposed to change the wood's properties. Greenheart has a fine texture and lustrous lus·trous adj. 1. Having a sheen or glow. 2. Gleaming with or as if with brilliant light; radiant. See Synonyms at bright. lus grain. Drying Tips Greenheart dries very slow. The U.S. Department of Agriculture, Forest Products Laboratory, recommends that lumber more than 1 in. thick be air-seasoned prior to kiln drying. They suggest kiln schedule T2-C2 for 4/4 stock and T2-C1 for 8/4 stock. Movement in service is rated medium. Greenheart can be difficult to work and even dangerous, as poisonous splinters can fly from the wood when being worked. Interlocked, cross and end-grains pose the biggest risk. Machining is made more difficult by the presence of an interlocked grain. The wood is rated moderately hard to work with both hand and machine tools, due in part to the density of the wood. It will dull cutting edges quicker than other woods, but it can be finished to a lustrous sheen. A Popular Name Greenheart appears to be a popular name for a variety of species. Tabebuia serratifolia is a tree native to Brazil. It is called pau d'arco pau d'arco (pō' därˑ·kō), n Latin name: Tabebuia impetiginosa; parts used: bark, heartwood; uses: this herb is controversial. , greenheart, iron tree, ironwood ironwood: see hornbeam. ironwood Any of numerous trees and shrubs, found worldwide, that have exceptionally tough or hard wood useful for timber, fence posts, and tool handles. , Surinam, lignum vitae and sometimes ipe. The tree is no relation to Ocotea rodiei. Cyclicodiscus gaburensis is also known as African greenheart. Editor's note: 107 Wood of the Month articles are now online, with more coming soon. Visit the Wood of the Month archive at www.iswonline.com. FAMILY NAME Ocotea rodiaei of the family Lauraceae. COMMON NAMES Greenheart, bibiru, sipiri, kevatuk, beeberoe, demerara Demerara (dĕmərâr`ə), river, c.200 mi (320 km) long, rising in the Guiana Highlands, E Guyana, and flowing N to the Atlantic Ocean. Georgetown, Guyana's chief port, is at the river's mouth. greenheart, demerara groenhart and sipiroe; also known by color, with names such as green, black, brown or white greenheart HEIGHT/WEIGHT Height varies from 70 ft to 130 ft, with long, straight, cylindrical boles 50 ft to 80 ft long, with average diameters of 3 ft. Average weight is 64 lbs per cubic foot. PROPERTIES Texture is fine and uniform. Wood has no odor or taste when dry. Wood splinters can cause poisonous reaction. Wood dries slowly; checking and end splitting may be a problem. Preboring is necessary, for nailing or for screws. Wood has medium movement in service. Wood is extremely durable, but very resistant to preservative treatment. Grain varies from straight to interlocked with a fine, uniform texture. |
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