326 



THE AGRICULTURAL NEWS. 



OCTOBEE 8, 1904. 



SCIENCE NOTES. 



Distribution of Essential Oils in Plants. 



[A?',^|The Pluirmaceutical Journal of August G has the 

 following extract on the above subject: — 



Continuing their investigation.s on the history of essen- 

 tial oil.s in [jlants, Charabot and Herbert state that after its 

 formation in the green organs, chieHy the leaf, the essential 

 oil is partly dissolved liy the water which circulates in the 

 plant. The chemical transformations which the terpene 

 compounds undergo are such that the essential oil contained 

 in the stem becomes less soluble than that contained in the 

 leaf. The deduction is drawn that a portion of the odorous 

 compounds migrates from the leaf towards the stem under 

 the influence of the laws of diffusion. An examination of 

 orange Howers and buds at different stages of growth leads 

 the authors to think that the petals of the plant contain the 

 greater portion of the essential oil of the flower, and contain 

 also the greatest percentage proportion of oil. During the 

 development of the Hower, the essential oil becomes richer in 

 esters of turjiene alcohols, in methyl anthranilate, and in total 

 alcohol. The ratio of the quality of combined alcohol to 

 that of total alcohol iiicre:ises ; in other words, esterification is 

 continued in the flower, but at a slow rate. The proportion 

 of geraniol increases, and that of linalool decreases, so that 

 the alcoholic nii.xture becomes richer in geraniol. {BitUetin nf 

 Roitsc-Bertmnd Fih, 1, 9, 13.) 



The Flowering of the Bamboo. 



The bamboos form an interesting and important group 

 of grasses, differing from other ordinary grasses in many 

 ways. They are the giants among grasses, the erect 

 sub-aerial stems of some species reaching a height of 120 

 feet, and a thickness of 12 inches. The floral structure also 

 differs from that of ordinary grasses, the number of stamens in 

 most species being six or more, while in other grasses 

 (including the sugar-cane) it is usually three. Again, the 

 fruit of some bamboos is a fleshy berry, while that of other 

 grasses is a hard, dry grain or 'caryopsis.' The economic uses 

 of bamboos in the East are too numerous to mention. 



An i)iteresting biological peculiarity of many larger 

 bamboos is seen in their flowering. For several j-ears the 

 plants grow vegetatively without flowering, and then in one year 

 the whole of them, at least all those in a district, will flower 

 together : Bninhusa 'irumhnacea, for e.xample, is said to 

 flower every thirty-two years. A correspondent in i^^atun of 

 September 1 gives some particulars with regard to this i)oint, 

 ■which is also dealt with at some length by Dr. (now Sir 

 George) Watt in his Dictionary/ of the Econoiaic Products of 

 India. The curious point about it is that plants raised 

 from cuttings always flower in the same year as the parent 

 plant even though they may be only one year old. After 

 flowering the bamboos usually die down. 



It is still doubtful whether this gregarious flowerin" is 

 really widespread or only local. It usually takes place in 

 a dry season when other crops are poor, and the large quantity 

 of bamboo seeds are used by the natives as food. As stated Ijy 

 Mr. Gamble in Xatme, 'information on the subject is being 

 gradually collected in India ; the dates of flowering of the 

 different species are, when obser\'ed by forest officers, 

 recorded in their journal, the Indian Forester, and the 

 behaviour of the clumps is being carefully watched, especially 

 as the dying off of the clumps of a species over large areas 

 may meap a serious dearth for several years of the most 

 useful material for the construction of native houses and of 

 many articles of common domestic use.' 



Another point of discussion is as to whether the bamboo 

 "flowe:-s when it attains a certain definite age (reckoned from 

 the seed, so that cuttings are of the same age as the parent 

 plant), or oidy at any period after it is mature when 

 conditions are favourable. With regard to this point 

 Dr. Watt says : ' Both may be true, and this is probably the 

 wiser solution of the ditficidty, that is to say, a bamboo may 

 not flower before it has attained a certain age, but its 

 flowering is not fixed sn arbitrarily that it cannot be retarded 

 or accelerated bj' climatic influences.' 



Reference will be found in the Ar/ricultural News 

 vVol. I, p. 39) to the flowering of a clump of bamboo-i in 

 Grenada. 



EXPERIMENTS IN ORCHARD CULTURE. 



A series of experiments in orchard culture has 

 been conducted at the Agricultural Experiment Station 

 of Nebraska, of which an account is given in Balk'tin 

 No. 79. The following summary of conclusions is 

 published for its general interest : but it must be 

 clearly understood that the existence of winter is an 

 all-important factor in these experiments which is 

 absent in similar exi)eriments in the West Indies : — 



"We may fairly say that the tests reported in this 

 bulletin indicate the best all-round method of cidture for 

 young orchards to be thorough cultivation in early sununer, 

 followed by a cover crop in fall, so far as tests covering only 

 a few years can prove any method Ijcst. 



A mulch of straw is known to keep the soil moist during 

 summer and it also protects tender roots in winter, but its 

 use will surely increase winter injur_y to tender tops' of trees 

 by prolonging fall growth. Ijcsides, a mulch induces .shallow 

 root develoiiment, which may result disastrously in later year.s, 

 and its use is out of the question in large orchards. 



Thorough cultivation protects trees against drought as well 

 as mulching, and keeps the roots from forming near the surface 

 of the ground. When cultivation is given in early sununer, all 

 that is necessary in order to furnish winter protection is to stop 

 cultivating in midsununer, grow a cover crop (weeds being 

 better than nothing) which will dry the ground in fall, 

 causing the new wood growth to rijien early in preparation 

 for winter and which will, by holding the snow or by matting 

 down to form a mulch, protect tender roots during winter. 

 Good cultivation in early sununer can often be given young 

 trees by growing some cultivated crop in the orchard. 

 Tender crops are best since they can not be sown so early as 

 to dry the ground .seriou.sly in spring and are killed by fall 

 frosts, thus preventing very late drying. Cropjiing with 

 corn, for- instance, insures fairly thorough early cultivation, 

 and corn is a fair substitute for a cover crop in fall and 

 winter. 



