Vol. X. No. 252. 



THE AGRICULTURAL NEWS. 



415 



named stem canker; it is of uncertain origin, but may be due 

 to physical causes. In the same article, mention is made of 

 what is possibly a fourth disease of lime roots, in Antigua 

 and Montserrat; it is associated with the presence of Fomes 

 lucidtis. 



ENTOMOCENOus FUUGi. Notcs on these useful species 

 may he found on pp. 62, 94 and 190. On the first-men- 

 tioned page reference is made to the green muscardine fungus 

 (Metarrhizium anisopUae), on frog hoppers in Trinidad. On 

 the second is an article dealing with general considerations 

 as to the use of fungi for controlling scale insects, giving 

 some account of recent experiments in Grenada and Harbados, 

 and recording the discovery of the shield scale fungus 

 {Cephalofpoiium lecanii) on the mealy shield scale (Proto- 

 pulvinaria pi/riformis). In the third reference, mention is 

 made of a new parasite, Ht/pochiella oxyspara, found on scale 

 insects in Dominica and St. Lucia, one of whose hosts is the 

 mango shield scale {Cocc-us mangiferae); while the others are 

 not yet known with certainty. An unidentified mycelium on 

 the larva of a beetle, Cryptorhynciis sp., attacking croton in 

 St. Vincent is also recorded. 



MISCELLANEOUS FUNGI. The following diseases are dealt 

 with on p. 190: fruit spot and die-back of the mango in 

 St. Vincent, probably due to Gloeosporium mangiferae; leaf 

 spot of Bengal beans, in Grenada, due to Cercospom sp; and 

 Guinea corn rust in Barbados, due to Puccinia purpurea, 

 with Barlura Jilum — another fungus— parasitic upon the 

 rust. On p. 222, is a note on white rust of sweet potatoes, 

 due to Cystop)us Ipouioeae-paiiduratae; while on p. 318 

 are observations on a species of Jew's ear fungus, Hirtuola 

 polytric}ui—& very common saprophyte on wood. 



MISCELL.4JJE0US ARTICLES. These Comprise the following, 

 and contain matter of mycological or pathological interest: 

 The Secretion of Poisons by Fungi, p. 62, with special refer- 

 ence to the Botrytis stage of Sclerotinias, to the fungus 

 {StereuiiL purpureum) causing silver leaf of various fruit trees, 

 such as the plum and apple, in Europe, and to Golletotrirhum 

 gloeos2Mrioides, the wither tip fungus of citrus; The Bracket 

 Fungi, p. 270; Recent Work on Bordeax Mixture, p. 302, 

 a review of some results obtained by Barker and Girningham; 

 Wounds in Plants and Their Treatment, Part I, p. 334, 

 Part II, p. 3.^0; and the Rotting of Timber and its Preven- 

 tion, p. 398. 



Oil From Grape Seed. — An oil of somewhat similar 

 type to that of the olive may be obtained from the stones or 

 seeds of the grape. During the eighteenth century the manu- 

 facture of this oil was an industry of considerable importance 

 in many towns in France, especially at Albi (Department of 

 Tarn). The seeds contt.in from 15 to 20 per cent, of oil, the 

 manufacture of which, thanks to modern processes, has been 

 revived in Italy during the last two or three years. Grape- 

 seed oil is coming into use for soap-making, as well as for 

 lubricating and lighting purposes. It is estimated that from 

 two to three million of quintals of this seed could be supplied 

 annually by France alone, which, if separated from the skins 

 of the grapes, would produce from 300,000 to 450,000 quin- 

 tals (say 6A to 10 million gallons) of oil The value of the 

 residuum after wine-making would be considerably enhanced 

 as a raw material for distillation. The brandy (eau-de-vie) 

 thus obtained would not only be of superior quality, but also 

 free from any disagreeable taste due to the essential oil of the 

 seed. {Journal of the Royal Society of Artt, November 17, 

 1911, p. 20.) 



GUAYULE RUBBER. 



Attention is given, in the India Rubber World for 

 October 1, 1911, to the recently published work of F. E. 

 Lloyd, entitled Guayule, a Rubber Plant of the Chihuahuan 

 Desert, and the following is taken from the matters presented. 



EARLY EXPORTS FfiOM MEXICO. Dr. Lloyd estimates tfcat 

 the total export of Guayule rubber from Mexico during the 

 four fiscal years ending June 30, 1909, was 20,000 short 

 tons, of which 80 per cent, was taken by the United States. 



YIELD. A further estimate is made of the weight of the 

 shrub that was required to produce the above amount of 

 rubber, and on a basis of a 7-per cent, yield, this must have 

 been 286,000 short tons. The return of rubber was higher, 

 however, in some cases, so that a re-estimate is made to the 

 eflfect that 225,000 short tons represents the quantity of the 

 plant disposed of, up to June 1909. 



SUPPLY OF THE PLANT. It Was estimated by Endlichthat 

 the original quantity of Guayule shrub represented 375,000 

 short tons of rubber, the calculations being based on a yield 

 in virgin fields of one fifth of a ton per acre, from 1,880,000 

 acres — the supposed area occupied by the plant in Mexico. 

 A re-estimate by Dr. Lloyd places the original quantity at 

 500,000 tons of rubber; of this it appears that about four 

 fifths have been consumed so far. 



CULTIVATION. Up to the present time, field operations 

 have been mainly concerned with the harvesting of the plant 

 in the quickest way — most generally by pulling it up by hand. 

 It is easily understood that the best method is to cut the 

 plants, in order that they may be enabled to spring again. 

 It is recommended that, at the first cutting, only plants at 

 least 16 inches in height should be taken. In five years these 

 will be replaced, under normal conditions, by a new crop of 

 plants over 16 inches in height, and these can then be har- 

 vested. It is considered that the maximum economic effi- 

 ciency of growth is reached at a height of between 12 and 16 

 inches. In the opinion of Dr. Lloyd, the ultimate solu- 

 tion of the raising of the shruli lies in its cultivation as 

 an ordinary crop. It has been established already that it 

 grows well under a system of irrigation in which proper 

 periods are included for the withholding of water. 



R.A.ISING SEEDLINGS. For this purpose the seeds are 

 planted in wooden trays partitioned into compartments by 

 paper receptacles, and the soil is watered from beneath. 

 When they are ready, the seedlings are placed out, still con- 

 tained in the receptacles in which they were grown. It has 

 been observed that germination takes place most readily, 

 and the seedlings grow best, during the summer months. 

 A method of transplantation that has been found to be 

 successful is to cut the plants back as far as the top of the 

 tap root, before placing them in the ground; in this case the 

 severed top is sent to the factory for the extraction of its 

 rubber. 



PROSPECTS OF GUAYULE CULTIVATION. So far, the 



facts which have been ascertained have not warranted the 

 making of cultural trials on anything but a small experi- 

 mental scale. It appears that successful cultivation is 

 mainly a matter of water-supply and the careful harvesting 

 of the plant. 



It may be mentioned that an account of the extraction 

 of rulrber frOm the Guayule plant appeared in this volume of 

 the Agrieidlural News, on page 229. It may also be stated 

 that the work which forms the subject of the above informa- 

 tion is also reviewed in the India- liuhi.er Journal for 

 September 16, 1911, p. 19. 



