762 Journal of Agriculture. [10 Dec, 1909- 



Mr. AlcxaiulL-r, in his Itttfr, raises several interesting points of vege- 

 table ph\siologv, concerning some of which Imt little ex]jeriniental in- 

 vestigation has as yet been carried out. 



When a root is cut, it certainlv renews itself, but its renewal would 

 not necessarily occur in the same wav as hai)])ens almve ground when 

 a limb is .severed. Below ground, instead of forming one main root to-- 

 replace the portion it had lost, the vine would ,be more likely to throw 

 out a bunch of small rootlets. These would not ]jenetrate to the same- 

 distance as the suppressed T)art and for some time, at least, their power 

 of supplying moisture and plant food, would be less. It is questionable- 

 whether this bunch of roots would, even after a considerable lapse of 

 time, perform its functions as satisfactorilv as the original root. It has- 

 long been held bv \iticultural authorities that a vine planted as a cutting 

 is of more robust ('(institution than one planted as a rootling — in the 

 case of the latter, the roots which were necessarilv cut l)ack on trans- 

 plantation would throw out a less normal system than that provided by 

 the original cutting. The vine planted as a cutting would be more 

 similar to a vine grown from seed — the natural means of reproduction of 

 the plant, and therefore the normal one. These remarks ripply tf> the- 

 principal roots of the vine. 



It must be remembered that the root s\ stem of the \ine is made up 

 of two groups, viz., surface feeders, which absorb the bulk of the plant 

 food substances — mainly at an early period of the yearly cycle of growth 

 - — and (ieep roots, which chieflv serve to supplv the necessary moisture- 

 in drv weather. The latter perform their functions throughout the- 

 summer. 



Analysis shows that,' in the great majoritv of our soils, the surface- 

 is richer than the subsoil, at least in nitrogen and often in phosphoric 

 acid also. As regards potash, the contrary is frequently the case — 

 especiallv where the subsoil is clavey. Abundance of the first-named 

 elements would tend to promote active root growth in the more superficial 

 layers. 



The influence of climate must be taken into account ; the feeding roots 

 of the vine are. no douljt, situated at a greater depth in arid districts 

 than in moist ones. 



The svstem of cultivation must also be considried. Ii-| most of the 

 warmer European wine districts deep cultivation (7 inches to 9 inches),, 

 at lea.st once a vear, is the rule, supplemented b\ sliallcw scarifyings. 

 This would })re\ent the development of roots near the surface. 



The case of a plot of vines, rogularlv submitted to such treatment 

 and therefore not permitted to have a superficial root system, is of course, 

 \-erv different from one which is never ploughed deeper than 4 or 5 inches, 

 as is the case in manv of our vineyards. In the latter case, the vines 

 would most probnblv suffer after an exceptional! v deep ploughing, at 

 least during the first season. 



The question of the best depth for culti\ati()n has received a con- 

 siderable amount of attention in Europe recently, as the outcome of the 

 opinions of M. Oberlin, of Colmar, who strongK rerommt nds shallow 

 cultivation. 



Professor Ra\az of Montpellier nuiilished, in 1905. an important work 

 on the whole subject, resuming its history and giving results of 



