Hence, at a relatively early stage, the USE will need to decide whether to sc.r.a.p some of the auto tires (figuring that it cannot keep the whole auto fleet running) in order to supply patch material for the heavy tires used in the USE"s military vehicles.
At the very least, all the spare auto tires in the car trunks can go to the rubber reclaiming plant. If there are around 1,200 cars (Mannington actually has more than that), then that will potentially yield 24,000 pounds of tires, and about 14,000 pounds (seven tons) of somewhat degraded rubber. If we decided to take the working tires off half those cars, that would be another 48,000 pounds of tires, and thus another fourteen tons of secondhand rubber.
One problem is that the Grantville encyclopedias are not very specific about the methods used for rubber reclaiming. EA suggests that the rubber is mechanically reduced to sc.r.a.p, which is then "heated with steam in the presence of strong chemicals, mainly alkali or acids."
If someone does have the Microsoft Encarta on CD, that gives additional information. It mentions the Chapman Mitch.e.l.l process, in which hot sulfuric acid is used to destroy tire fabric and restore rubber plasticity, and the Marks "alkaline-recovery process."
In general, the rubber is not going to be restored to its original unvulcanized state, and hence it is more difficult to use. Usually, the reclaimed rubber is used as an extender, together with fresh rubber.
Proposal Our initial natural rubber industry development strategy should be: (1) use rubber subst.i.tutes (e.g., leather) whenever possible; (2) conserve and reclaim up-time rubber; (3) cultivate milkweed at home; (4) send raiding parties into central America to collect Castilla rubber; and (5) attempt to reach the Hevea rubber of the Amazon by a back-door route.
Once we have built enough steamships (warships as well as merchant ships) so we can spare a few for extra-European ventures, we should send an expedition-in-force to the Amazon to collect Hevea seeds, and then one to Africa or Asia to establish plantations and collect wild rubber (and rubber tree seeds). Ideally, we would also have sufficient medical resources so as to offer this expedition some protection against the many diseases that hamper seventeenth-century international trade.
If we are allowed to trade freely for wild Brazilian Hevea rubber, and to promote efficient tapping practices, it should satisfy our needs for rubber up until annual world consumption reaches the 30,000 to 40,000 pound range (the peak Brazilian wild rubber production). After that, the development of alternative rubber sources is essential. Hence, at the end of the first decade, we need to decide whether to establish Hevea plantations in Africa or southeast Asia, or to pursue synthetic rubber.
While an investment in the rubber industry is definitely going to qualify as one of USE"s riskier commercial ventures, investors can at least be confident that if they are successful, the USE government and private industry will be sitting on their doorstep, anxious to do business.
Table 1: Listed Rubber Sources: Where and How to Find Them Rubber Plant (Note A) Range: Range (to extent known in Grantville); Descriptive Material (as available in Grantville (Note B) Hevea brasiliensis Para Rubber Tree (major source in OTL) (Often confused with other producing Hevea species, such as H. guianensis, H.
benthamiana, H. pauciflora; H. spruceana is a poor producer.) Range: W: South America (EA). Range depicted in CE (probably includes other Hevea species). C: Sri Lanka, Malay Archipelago (EA), Straits Settlements, Malay States, Ceylon, Java, Sumatra, Borneo, Burma, south India, West Africa (especially Gold Coast), Congo, tropical Australia (EB11) Range depicted in CE and WBE. There are reports of Hevea paucifolia [sic, pauciflora] and guianensis in British and French Guiana, respectively (EB9) Descr: EB11 has 1/4 scale drawing of leaves, fruit and seeds; photo of plantation trees; text. EB9 has scale drawings of leaves, male and female flowers, ripe fruit, and seed.
Manihot glaziovii Ceara or Manioba Rubber Tree Range: W: Brazil (EA): Northeast Brazil (EB11). Ceara is province of modern Brazil.
C: Ceylon, India (Madras), West Africa, East Africa, Nyasaland, Mozambique (EB11) Descr: EB11 has scale drawings of branch with flowers, fruit, seeds; photo of tree; text.
EB9 has drawings of tree, young leaf, inflorescence, half-ripe capsule, male and female flowers, seed, and seed section.
Castilla elastica Panama, Castilla, or Ule Rubber Tree (Other Castilla species produce rubber, e.g., C. ulei.) Range: W: tropical America (EA); Costa Rica, Guatemala, Honduras, Mexico, Cuba, Haiti, Panama, Nicaragua and, in South America, west of the Andes, especially Peru (EB11) and Ecuador (EB9). Mexican occurrence depicted in CE.
C: West Indies (esp. Trinidad and Tobago), south India, Ceylon, East and West Africa, Nyasaland (EB11) Descr: EB11 has scale drawing of leaf, twigs with male and female flowers, seed; photo of tree; text. EB9 has drawings of young leaf, seeds, margin of leaf, female flower. EA has description under "Castilla Rubber Tree."
Ficus elastica Rambong, a.s.sam or Indian Rubber Tree Range: W: Southeast Asia (EA); India, Ceylon, Sumatra and Java, Burma, Malay archipelago (EB11) C: West Africa and Egypt ("but not very successful" in Africa). Also an ornamental in Europe.
Descr: EB11 has scale drawing of leaves on twig; photo; text. EA has description under "Rubber Plant."
Funtumia elastica Lagos, African or Silk Rubber Tree (F) Range: W: central regions of east and west Africa (Uganda to Sierra Leone). Range depicted in CE and WBE. C: Gold Coast, south Nigeria. Descr: EB11 has scale drawing of twig with flowers, underside of leaf, fruit; photo of tree; text.
Rubber Vines (EA, CE, EB11) Range: W: Africa (EA) Africa and Asia (EB11, see note D below) Descr: EB11 has scale drawing of twig with flowers, fruit. (For the African Landolphia owariensis)
Parthenium argentatum Guayule (EA, CE, EB11) Range: W: Mexico and Texas, Chihuahuan Desert (EA). Range depicted in CE.
Descr: text (EA, "Guayule")
Raphionacme utilis Ecanda Range: W: Portuguese West Africa.
Descr: None, but "Ecanda" may be the native name.
Bleckrodea tonkinensis Range: W: Tonkin (EB11) Descr: None, except that it is a large tree.
Hancornia speciosa The Pernambuco or Mangabeira Rubber Tree, Range: W: the plateau region (3,000 to 5,000 ft. above sea level), from Pernambuco to Rio de Janeiro, in Brazil. (EB11) Descr: text.
Sapium species Range: W: Columbia and Guiana, especially S. jenmani of Guiana (EB11).
Descr: just "large trees resembling Hevea."
Taraxac.u.m kok-saghyz Russian Dandelion (EA, CE) Range: W: Turkestan (EA) Descr: none, but similar to common dandelion.
Solidago Goldenrod (CE) Range: Familiar American plant.
Asclepias syriaca Common Milkweed Range: Familiar American plant.
Table 2: Productivity of Identifiable Rubber Plants Rubber Plant (Note A) Collection: Methods Density: (Trees per Acre, Tr/Ac); Age in years to First Tapping (y) Yield/Tree: Rubber, pounds per tree per year Yield/Acre: Rubber, pounds per acre per year (Note C)
Hevea brasiliensis Para Rubber Tree (major source in OTL). (Often confused with other producing Hevea species, such as H. guianensis, H. benthamiana, H. pauciflora; H. spruceana is a poor producer.) Collection: Incision tapping by Ridley method on alternate days (56 g latex per tap)[EA]; V-, herringbone or spiral cuts [EB11], Felling is ineffective for rubber collection.
Density: W: tap at 10-15y [EB11]1 Tr/Ac [Dean10], C: 150 Tr/Ac; tap 6-7y [EB11]; 150 Tr/Ha; tap at 5-7y, productive for 30-40 more yrs. [EA]; 100 Tr/Ac [Enc]; 100 Tr/Ac [WBE];.
Yield/Tree: W: 10-15 [EB11]; 2-10 [Dean 10], C1910: 1-2 [EB11]; 0.41-6.76 (6-12 yrs, Malaysia and Ceylon)[Br 126-7]; C1920: 5 [TW301]; CM: 6 [EA]; 4-5 "ordinary" or 12- 16 "selected and bud grafted" [CE]; Yield/Acre: W:2-15 [Calc, EB11+Dean], C1900: 382* kg/Ha [EB], C1910: 128-221 (6-7 yr., Malaysia) 105-200 (Ceylon) 105-768 (6-12 yr., combined), [Br126-7] C1940: 342- 513* [PH273]; CM: 800-1,000 (avg), 2000+ (top) [EA]; 400-2,000-3,000 [Enc];1,800[WBE]; 798-2,280* [PH273]
Manihot glaziovii Ceara or Manioba Rubber Tree Collection: Tapping Density: tap at 5y [EB11]; 700+ Tr/Ac [PH267]; 320 Tr/Ac [Br150-1]
Yield/Tree: 1+ [EB11]
Yield/Acre: C: 88-176 Germ E Africa (5-8 yr.)[Br150-1]
Castilla elastica Panama, Castilla, or Ule Rubber Tree (Other Castilla species produce rubber, e.g., C. ulei.) Collection: Incision tapping [EA]; herringbone or spiral cut [EB11]; or felling [PH16]; 1- 4 taps/y [PH102]
Density: tap at 6y [PH109] 8y [PH104]; 50 [PH267] or 100-120 Tr/Ac [PH109]; 400- 700[TW32]; 200/Ac [TW279]
Yield/Tree: W:12[PH93]; 40 [EB11](tree killing tap?), C:0.93-1.01* [PH109], 0.1- 1.1*/tap [Br222], 0.38-1/tap [TW150], 0.1-0.4 (6-10y)[TW279]; 0.13/tap [TW32], Felled Tr: max 100 [PH16] 51-73* [PH109]; avg 15-20 [TW148]
Yield/Acre: C:50 [TW279]
Ficus elastica Rambong, a.s.sam or Indian Rubber Tree Collection: Shredding of leaves and shoots [EA]; tapping [EB11] Density: 50 Tr/Ac [PH267]; tap @10y[EB11], can"t tap each yr. [Br233]
Yield/Tree: C: 5-10 [EB11], 0.65-2.3 [Br232]
Yield/Acre: C: 500-1,000 [calc]; but 13-52 [Br232]
Funtumia elastica Lagos, African or Silk Rubber Tree (F) Collection: Incision tapping, herringbone [EB11]
Density: tap at 20y [EB]; at 5y [Ch193]; tap 2-3 times/y [Ch161]; tap 1-2/y [Br161], W: up to 150-250 Tr/Ac [Ch36]; C1910: 450-600 [Ch97]
Yield/Tree: Tapped (3/yr) [email protected], [email protected] 8y, [email protected] [Ch161]; ~1/tp [Br176] Felled Tr:0.64 [Ch161] 4.5-6.5[Br176]
Yield/Acre: W: ~150-375 [150-250 x 2-3 *.5] C: ~450-900 [450-600 x 2-3 *.5]
Rubber Vines (EA, CE, EB11) Collection: Cut stems; or macerate roots or rhizomes in hot water [EB11]
Density: ?
Yield/Tree: 6-7/Pl [PH40]; 0.06-0.18/Pl [Br197]
Yield/Acre: ?
Solidago Goldenrod (CE) Collection: harvest and extract resin with acetone and rubber with benzol [PH268]
Density: 10-20,000 Pl/Ac [PH268]
Yield/Tree: Yield/Acre: C: 100 in 1929, >300 in 1934 [Van293-300; Bal398, 411]
Asclepias syriaca Common Milkweed Collection: harvest and extract Density: 10-20,000 Pl/Ac [PH268]
Yield/Tree: Yield/Acre: C1940: 114-171* [Whiting]
Productivity of Trees for Which Description Is Limited Hancornia speciosa The Pernambuco or Mangabeira Rubber Tree, Collection: Incision Tapping (8 oblique cuts all around trunk)[EB11]
Density: Yield/Tree: Yield/Acre:
Parthenium argentatum Guayule (EA, CE, EB11) Collection: Shredded; leached with hot water [EA]
Density: C: 3-5y [EA];4-5y [Van284]; 5-9y [PH233]; 8,000-16,000 Pl/Ac [PH267];7,000-11,000 Pl/Ac (Van284, 308) Yield/Tree: Yield/Acre: C: 137-241 [PH233], 325-400 [Van284]
Taraxac.u.m kok-saghyz Russian Dandelion (EA, CE) Collection: Shredded; leached with hot water[EA]
Density: Yield/Tree: Yield/Acre: C1940: 285 (Suomela)
Notes to Tables 1 and 2: (A) With the exception of milkweed, the cited plant names appear in the Encyclopedia Americana (EA), the modern Encyclopedia Britannica (EB), the Eleventh (EB11) or Ninth (EB9) editions of the Encyclopedia Britannica, the World Book Encyclopedia (WBE), or Collier"s Encyclopedia (CE) as sources of rubber.
There are three plants which produce nonelastic rubbers which can be used for insulation, belting, etc. Trees of the genera Palagium and Payena, found in the Malay Archipelago, produce gutta percha. Manilkaea bidentata, found in tropical America, produces balata. Manilkaea zapota, the Sapodilla Tree of Mexico and Central America, produces chicle (mostly used in chewing gum). (EA) (B) The wild (W) and cultivated (C) range information is primarily from EA and EB11. Info on sites of cultivation includes experimental plantings which may not ultimately have proven successful. Descriptions of the plants are from EB11, unless otherwise stated.
(C) In general, productivity data is not available in Grantville; the one exception is Hevea.
The encyclopedia data is cited in the main text. "Enc" is Microsoft Encarta Encyclopedia. The remaining data was collected from various industry sources. "PH" is Polhamus; "Br" is Brown, "Ch" is Christy,"TW" is Treadwell, "Van" is Vanderbilt, "Bal" is Baldwin. W: wild production.
C: cultivated. C1910: cultivated production circa 1910. C1940: cultivated production circa 1940.
CM: cultivated production in modern times, shortly before ROF. "Tr" means tree, "Pl" means plant. In converting metric to English units, I used 2.5 acres per hectare and 2.2 pounds per kilogram. One kilogram per hectare equates to about 1.14 pounds per acre. Note that productivity is dependent on the location, the age of the tree, the frequency and method of tapping, and so forth.
(D) Various rubber producing vines of the family Apocynaceae, especially (1) the genus Landolphia, and its species L. owariensis, L. heudelotii, L. kirkii and L. dawei, in tropical Africa, (2) the genera c.l.i.tandra and Carpodinus in West Africa, (3) the Forsteronia gracilis of British Guiana, (4) the Forsteronia floribunda of Jamaica, (5) the genera Willughbeia and Leuconitis of Borneo, (6) Parmeria glandulifera of Siam and Borneo, and (7) Urceola esculenta and Cryptostegia grandiflora of Burma (EB11). Note that EA states that Cryptostegia grandiflora is found in Africa.