Vol. XI. No. 265. 



THE AGRICULTURAL NEWS. 



199 



INFORMATION CONCERNING THE 

 MANIHOTS. 



The following notes refer chiefly to Jequie and Keman.so 

 M.ihicoba rubber {Manihot dicliotoina and M. piauhycnsis), 

 and are based on details concerning these plants supplied 

 directly to the Commissioner of Agriculture, by Mr. Gilbert 

 Railton. as well as those contained in an article in Trojncal 

 Life, for January 1912, written by Mr. Railton. It may be 

 said that Mr. llailton has had useful experience in growing 

 the Manibots in the hinterlands of Brazil. 



Dealing generally with the Manihots, it is the opinion 

 of this authority that the claims for a production of rubber 

 equal to that from Hevea are not founded on fact; nor is it 

 necessarily true that the returns from ibe specie.s mentioned 

 are far greater than those from Ceara rubber (J/. Gtaziouii). 



Both J/, dichotoma and M. piaultyensis grow well in 

 dry climates, and do not suffer groat damage from the condi 

 tions of ordinary drought. They prefer the slopes of hills 

 and the valleys near them, and have been found growing 

 successfully up to an altitude of as much as 4,000 feet. 

 Land that is likely to become waterdogged, even if the condi- 

 tion is only temporary, is entirely unsuitable to th'se species. 

 With respect to the former plant, it is stated by Mr Railton 

 that it may thrive on poor pasture land, but lie lays stress on 

 the particular .suitability of recently burned land to the needs 

 of this tree, as a seedling. 



Reference to the article in Tropical Life will show that 

 seeds required for planting should be allowed to mature 

 thoroughly in the sun, or be kept on a dry floor for at least 

 nine months atter falling, in order that a regular germination 

 may be obtained. It is lecommended that they should be 

 sown two or three in a hole at least an inch deep, at stake, 

 in the places which the plants will occupy permanently. 

 The employment of seed beds and subsequent transplanting 

 is discouraged, chiefly because the length of the tap root of 

 seedrings is so great and the bark so tender that it is easy to 

 cause injury from which the tree will not recover. The use 

 of cuttings is discouraged to an even greater degree; plants 

 grown from them develop a shallow r"0t system which 

 makes it possible for the tree to be blown over by the first 

 high wind; this objection also applies to the transplanting of 

 seedlings. In order to ensure and encourage germination, the 

 seeds should be soaked in water for one to two days, just 

 before they are sown; in some cases a longer soaking than 

 this has been found successful 



The objections that have been stated in connexion with 

 the use of seedlings and cuttings, for planting, apply equally 

 to the employment of stumps, which in the same way produce 

 plants of inferior growth and having a badly developed root 

 system. 



Practice has shown that J/, dichotoma and M. piauhyen- 

 sis may be planted much more closely than Hevea brasili.etisis 

 and M. Gladovii; ihey may be placed as near as 7 feet 

 X 10 feet. 



The amount of weeding that is required will depend 

 naturally on the conditions under which the plants are grown. 

 For the stage to be reached at which weeds will be kept 

 down by the shade from the plants themselves generally 

 requires a period much longer than a year; though assertions 

 are sometimes made that the shorter period is sutticient. 



Dealing particularly with M. dic/wtuiiia, it is generally 

 agreed that this flourishes on good clay soil; it is considered 

 by Mr. Railton that it does not pay to tap this species before 

 the trees are six years old. 



M. piau/iyensis is suited more especially for the lighter 

 soils; I he height attained by it is not as great as that reached 



by M. dichotoma. In regard to the rate of growth, .Mr. Railton 

 has observed trees, that had received good care, with 

 a diameter of 25 to 28 inches, the trees being six to seven 

 years old. At this stage the height of the uabranched 

 portion of the main stem was about 6 to 9 feet. 



CANDELILLA WAX. 



Notes on the candelilia plant and its wax have 

 been given several times in this journal (see AgriciU- 

 fural Xews, Vol. XI, p 7.3), as the matter is of partic- 

 ular interest in relation to the fact that it has been 

 introduced into AuU^na, .S^ Kitts and Montserrat by 

 thi.s Department. In coniinuation, the following is 

 taken from the Bulletin of the Imperial Institute, 

 Vol. X, p. 128, just issued: — 



In a previous number of this Bulletin (1909, p. 411) 

 a note by the late Dr. Ol.'-son Seffer was printed, giving 

 information regarding the botanical origin, method of pre- 

 paration and characters of this wax. Dr. Seffer gave 

 Enphnrhia antisyphilitica Luce, as the source of the wax, 

 but other authorities have attributed it to Pedilanthus 

 jiai'onif, Boiss. and Euphorhia ccrifera, and it appears that 

 the confusion may be due to the fact that in Mexico the 

 natives apply the name ' candelilia ' to a number of widely 

 dirt'erent plants. 



A pamphlet has been published recently by the National 

 Medical Institute in Mexico, and in this, on the authority of 

 I'rofessor Alcocer, the i)lant, yielding the wax is given as 

 Eupliorhia cerifera. The following additional particulars are 

 summarized from the pamphlet already referred to. 



The wax can be extracted by cutting up the plant into 

 small pieces and either wrapping in wire cloth and immersing 

 in boiling water, when the melted wax rises to the surface and 

 can be skimmed off, or by subjecting the mass to live steam 

 in order to melt the wax, which can then be separated from 

 the condensed water. The impure wax so obtained is 

 purified by re-melting and filtering through charcoal mixed 

 with iron filings; it then varies in colour from greenish-yellow 

 to almost chocolate black, but can be partially bleached to 

 such an extent as to compete with carnauba wax. The 

 candelilia wax is not so hard or brittle as carnauba wax. 

 The composition is said to be affected by the age of the 

 plants, the region where they grow, and the time of year 

 they are collected, but it also seems likely that the great 

 differences that plants show in this are at least in part due 

 to the differences in botanical origin of the samples examined. 



According to Sanders the wax contains myricyl alcohol 

 and the hydrocarbon hentriacontane. 



The wax is said to be useful for a variety of purposes, 

 among which may be mentioned the manufacture of boot 

 polishes, sealing-wax, insulating materials, and varnishes. 



The wax has appeared on the Hamburg market 

 {CJcemisl and Drugyist, 1910, p. 59), and at first sold at 

 about 77s per cwt., since manufacturers preferred carnauba 

 wax, as its properties are well known to them. Recently, 

 however, candelilia wax has sold in Hamburg at 1 1 5s. per 

 cwt., so that it has apparently found definite uses in Germany, 

 probably as a substitute for carnauba wax. 



According to the British ViceConsul at Monterey (Board 

 of Trade Journal, 1911, p. 430), the supply of the can- 

 delilia plant is practically inexhaustible, and there are now 

 four factories at Monterey extracting the wax, two of which 

 are said to be shipping the product to the United Kingdom. 



