Gums, Resins, 



106 



[Fee. 1908. 



A memorandum on the Guayule, pre- 

 pared at the instance of H. M. Envoy 

 Extraordinary and Minister Plenipoten- 

 tiary, Mexico, by Mr. Vice-Consul 

 Kennedy, on information furnished to 

 him by Mr. Adolph Marx, the manager 

 of a Mexican company for the export of 

 this rubber, was forwarded to Kew from 

 the Foreign Office, on March 22nd, 1907, 

 together with specimens of plants of 

 Guayule, determined as Parthenium 

 argentatum. and of the Mariol P. inca- 

 num, a species apt to be confused with 

 Guayule. From this memorandum it 

 appears that "the first shipments of 

 Guayule rubber to Europe (1902) were 

 received with scant favour, and the 

 shippers were extremely glad to at last 

 get an offer fiom a London firm of 6d. 

 per pound. A few months later a 

 German manufacturer offered Is. per lb. 

 for the rubber, whilst an American 

 offered 25 cents gold per lb. At the 

 beginning of 1903 the same American 

 offered to take the whole output of the 

 factory at 40 cents per lb. Since that 

 date, as manufacturers have become 

 accustomed to this rubber, the price has 

 steadily advanced until 1906, when the 

 highest price was reached, viz., 2s. 9d. 

 per lb. Guayule or the Parthenium 

 argentatum is a shrub growing to about 

 3 feet high at maturity. It is of very 

 slow growth, and the samples accom- 

 panying this memorandum are probably 

 at least 30 years old. From the first 

 year, when only about 6 inches high, and 

 with a very thin stem, it gives both 

 flowers and seed, and so on every year, 

 and as it cannot be used for extracting 

 rubber until the eighth year, this gives 

 the plant ample time to produce, the 

 seed being blown about by the wind. 

 Up to the third year the plant contains 

 no rubber whatever, and from the third 

 to the eighth year the percentage of 

 rubber is small. A good well-matured 

 plant will contain as much as 10 per cent, 

 of its height in rubber. The best process 

 for extraction is that originally employed 

 by the Anglo-American Co, viz., mace- 

 ration of the plant, and extraction of 

 the rubber by steaming in an alkaline 

 solution. Unless the shrub is recently 

 taken from the ground, the quality and 

 quantity of rubber obtained is inferior. 

 From several factories in operation, and 

 one in course of constr uction, the esti- 

 mated total production from all sources 

 will not be less than 300 tons per month. 

 At present there is sufficient raw 

 material in sight to supply all these 

 factories for several years, say three or 

 four, but there is no plantation of 

 Guayule to make good the plants used 

 up ; it is only a question of time when 

 this source of rubber will be almost 

 entirely exhausted. The Guayule shrub 



is only found in the colder parts of the 

 Republic, and is not met with the south 

 of the Tropic of Cancer. It is principally 

 obtained from the States of Zacatecas 

 and San Luis Potosi. Mariola is another 

 shrub which can only be mistaken for 

 Guayule from the similarity of the colour 

 of its leaves, &c, especially in the wet 

 season. It grows in the same region as 

 the Guayule. The Mariola also contains 

 rubber, but in such small quantities 

 that it is not worth while to extract it. 

 According to "The Mexican Investor" 

 of March 23rd, 1907, it appears that 

 during the year 1905 a factory in 

 Germany, backed by large financial 

 interests, for the extraction of rubber 

 from Guayule, experienced its most 

 profitable run. The shrub was bought, 

 baled, and shipped by Mr. Oton Ketter- 

 feld, who traversed most of the interior 

 where Guayule was known to grow, and 

 who secured many thousand tons at 

 prices that look ridiculously low at the 

 present time. This German enterprise 

 was kept very quiet, and must have 

 made much money, until in September 

 the Mexican Government put an export 

 duty of 15 pesos a ton on the shrub 

 which, with the freight rates, made 

 further shipments unprofitable. The 

 following article, from the pen of Dr. P. 

 Olsson-Seffer, Director of the Zacualpa 

 Botanical Station and Rubber Labora- 

 tory in the Republic of Mexico, which 

 appeared in a recent number of " The 

 Mexican Investor " sums up the present 

 prospects of the Guayule industry. The 

 supply of Guayule has been greatly over- 

 estimated, principally because of the 

 confusing of Guayule with another 

 species of the same genus, Parthenium 

 incanum, H. B. K., which is far more 

 abundant and grows all through the 

 Guayule territory. This has been esti- 

 mated to as much as 28,000 square miles, 

 but it must be remembered that the 

 patches of Guayule are far apart, and one 

 can travel over miles in the Guayule 

 country without seeing a single speci- 

 men. The general estimate of Guayule 

 on the acre is from 400 to 700 lbs. taking 

 an average for large areas. This is 

 undoubtedly too high an average. By 

 actual count in very favourable localities 

 I have become convinced that even under 

 the best conditions not more tha i 1,500 

 pounds can be obtained per acie from 

 the Guayule patches, and these con- 

 stitute less than one-tenth of the total 

 area of the territory, where the plant 

 occurs. That my estimate in this regard 

 is upheld by others who have investi- 

 gated the matter and expressed an un- 

 biased opinion is shown by the following 

 lines, translated from an article by Dr. 

 Enlich, in Dtr Trofjenflanzer, 1905, pp. 

 233-247. The author says in part :— 



