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Rubber Tree Growing

Hevea trees are ready for tapping about 5 to 6 years after planting. This has been a focus of research at the RRIM, and certain clones can now be tapped in [Pg.1032]

After a year in the nursery, the young plants are transplanted to their final fields, and as they mature they are thinned out to 150 to 200 trees per acre. Research on higher density plantings are continuing 225 trees per acre seems possible in the near future. Fertilizer requirements vary depending upon the soil, but phosphate fertilizers are most commonly used. [Pg.1033]


Hevea rubber from uncultivated trees growing in the Amazon Valley of Brazil and exported from Para, a town at the mouth of the river. Para rubber was the best variety of all wild rubber but the advent of plantation rubber steadily reduced its importance until it is now of no significance in world rubber production. [Pg.46]

A disease of rubber trees affecting the pods and leaves. The resulting pod-rot and leaf-fall seriously reduces the latex yield. It is common in most rubber growing countries with, until recently, the exception of Malaysia, where urgent... [Pg.47]

Natural rubber obtained from cultivated trees as opposed to that obtained from trees growing wild in the jungle. The size of a plantation varies from the large estate of several thousand acres down to the smallholdings of a few acres worked by the owner and his family. Such smallholdings produce a significant proportion of the world s NR output. [Pg.47]

Natural rubber obtained from trees growing wild and not cultivated in either plantations or native small holdings. The output of wild rubber is now insignificant. [Pg.72]

Rubber comes from trees that grow in the tropics.The rubber tree has a type of sap, called latex, which oozes out of the bark and can be collected without hurting the tree. Rubber has been used by Indians in North America, Central America, and South America for hundreds of years to make balls and waterproof clothes. When Europeans came to the Americas, they used rubber for the same things.They also used rubber to rub out pencil marks, which is where the name comes from. [Pg.103]

A number of plants and some trees contain a white, milky liquid that is released when the stem or bark is cut. The liquid is called a latex from the Latin meaning liquid. Common sources include dandelions, milkweed, goldenrod, and potted rubber plants. Rubber trees, from which substantial quantities of latex can be harvested, grow in some tropical areas of the world. A major constituent of this latex is a homopolymer of isoprene (2-methyl-1,3-butadiene), called polyisoprene. Polyisoprene, as well as a number of other elastomers, has a carbon-carbon double bond in every repeat unit. The properties of polyisoprene are the result of the presence of these double bonds. Just as stereochemistry plays a critical role in both proteins and polysaccharides, we will see its importance here. [Pg.41]

This is the other natural rubber used in making chewing gum. It is produced from the sap of Dyera costulata of the genus apocyanesas. This tree grows in the Far East. The crude product is processed by a system involving the injection of steam into the raw material. [Pg.58]

Caoutchouc—India-rubber—is a peculiar substance existing in suspension in the milky juice of quite a number of trees growing in warm climates. It is, when jiure, a mixture of two hydrocarbons—caoutchene, Ci Hic, and isoprene, CsHs. [Pg.455]

Natural rubber is obtained from the juice present in various trees and shrubs which grow best in tropical countries. On account of the importance of rubber commercially the trees which yield it are grown systematically on plantations formerly the supply was obtained from natural forests. The intensive cultivation of rubber trees has had a marked effect in lowering the price and insuring a steady supply of rubber. [Pg.69]

Natural rubber of the best quality is prepared by coagulating the latex of the Hevea brastliensis tree that is primarily cultivated in the Far East. However, there are other sources such as the wild rubbers of the same tree growing in Central America, guyayule rubber coming from shrubs grown mostly in Mexico, and balata. Balata is a resinous material and carmot be tapped like the Hevea tree sap. The balata tree must be cut down and boiled to extract balata that cures to a hard, tough product used as golf ball covers. [Pg.453]

As rubber plantations are currently expanding to new areas under drier climatic conditions than traditional ones (north-eastern Thailand, Mato-Grosso in Brazil, north-western India), the performance of rubber trees under water stress has become a major issue. Two main traits are to be considered performance (the ability to transfer water and grow under water stress) and resistance (the ability to avoid damage and survive under water stress). Performance mainly relies on the conductivity of the hydraulic system from root to leaf, whereas resistance mainly relies on susceptibility to cavitation, leading to embolism, within xylem vessels. Stomatal closure occurs to avoid severe cavitation. Hence, differences in susceptibility to cavitation among rubber clones are likely to induce differences in resistance to severe water stress. [Pg.344]

Natural rubber can be obtained from nearly 500 different species of plants. The outstanding source is the tree Hevea brasiliensis, from which comes the name Hevea rubber. The tree grows best in damp, warm climates. It was first cultivated in Brazil and then imported to the Malay Peninsula, where the bulk of the world s rubber came before World War II. [Pg.364]

The natives of tropical America were preparing articles from the rubbery exudates of Hevea spp. (Euphorbiaceae) and Castilla spp. (Moraceae) trees well before discovery by Europeans in the early 17th century. Following the developments of vulcanization and other treatments, an enormous exploitation of rubber trees, particularly of Hevea brasiliensis, growing in the delta of the Amazon River and in its upper reaches west of Manaus, took place from 1827 onward. Large fortunes were made by a few European entrepreneurs at the expense of the lives of many local and imported laborers. After some difficulties, rubber trees were cultivated in Malaysia in 1880, and subsequently in neighboring countries, from which most of the natural rubber of today is derived. Following severe competition from syn-... [Pg.9]

Oriental lacquer is an emulsion, the sap is obtained by tapping lacquer trees in the same way that natural rubber is harvested from rubber trees. A Rhus vemiciflua tree can grow to a height of 30 feet, its leaves, blossoms and seeds are shown in Figure 3. After ten years of growth, the stem of the lacquer tree is mature enough, it can be cut and a sap oozes out of the tree which is similar to the sap from the rubber tree. [Pg.424]

Hevea rubber is undoubtedly one of the unique crops of history and of all agriculture, and one of the most interesting. It is not easy to produce rubber. Research is the tool by which it is possible to grow vast acreages of the tree as a profitable crop. This could never have been done without the past /and present intensive investigations of careful scientists over more than 30 years. Repeated reference in the literature indicates that diseases are the limiting factors in natural rubber production, and that planters owe a debt to disease-control workers. [Pg.41]

Natural rubber can be found as a colloidal emulsion in a white, milky fluid called latex and is widely distributed in the plant kingdom. The Indians called it wood tears. It was not until 1770 that Joseph Priestly suggested the word rubber for the substance, since by rubbing on paper it could be used to erase pencil marks, instead of the previously used bread crumbs. At one time 98% of the world s natural rubber came from a tree, Hevea brasiliensis, native to the Amazon Basin of Brazil which grows to the height of 120 ft. Today most natural rubber is produced on plantations in Malaysia, Indonesia, Singapore, Thailand, and Sri Lanka. Other rubber-bearing plants... [Pg.330]

Uses of sulfur. In the elemental form, sulfur is used (1) in the vulcanization of rubber (2) in the manufacture of black powder (3) as a fungicide (in powder form), particularly in growing grapes and (4) as lime-sulfur spray for fruit trees. Although the preceding uses require considerable amounts of this element, the great bulk of the world s production of sulfur goes into the manufacture of sulfur dioxide, which may be used as such or converted to other industrially important sulfur compounds, some of which are discussed later. [Pg.586]

The production process starts with the trees. Over the years considerable biological research has been done to produce trees that grow faster, produce more latex, and are resistant to wind and disease damage. Once such an improved tree has been identified, buds are grafted from the tree onto root stock. All such trees are referred to as clones and will have the same characteristics. It typically takes 6-7 years of growth before a tree is ready for rubber recovery. Peak rubber production is reached at 12-15 years of age. Another major development in improving tree performance has been the use of tree stimulants, which... [Pg.696]


See other pages where Rubber Tree Growing is mentioned: [Pg.265]    [Pg.32]    [Pg.32]    [Pg.33]    [Pg.40]    [Pg.91]    [Pg.265]    [Pg.349]    [Pg.19]    [Pg.275]    [Pg.689]    [Pg.58]    [Pg.31]    [Pg.63]    [Pg.344]    [Pg.403]    [Pg.286]    [Pg.1032]    [Pg.1033]    [Pg.1050]    [Pg.120]    [Pg.882]    [Pg.25]    [Pg.598]    [Pg.1017]    [Pg.737]    [Pg.19]    [Pg.351]    [Pg.34]    [Pg.36]    [Pg.38]    [Pg.247]   


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