10 Sept., 1917.] Spring Grafting of the Vint. 565 



A simple expedient, which appears to have been first proposed by 

 Felix Sahut, enables this difficulty to be overcome.* All that is necessary 

 is a tin or galvanized iron tube about 12 inches high and 6 inches in 

 diameter — a 7 lb. golden syrup tin, the bottom of which has been re- 

 moved, will do — and a load or so of sand. The method is illustrated 

 in Figure 5. The tube is placed around the graft and its stake. It 

 is then mounted up outside, to the level of the top of the sicion, with 

 the ordinai-y soil of the vineyard, which should be broken up and pul- 

 verized as completely as possible; the interior of the tube is tlien filled 

 with sand so as to completely cover the graft and the whole of the scion. 

 The tube is now withdrawn and placed around the next graft, which is 

 similarly treated, and so on. 



In wet springs it is possible that greater certainty of success would 

 be insured bv covering the mound with a hollow cone made of water- 

 proof ])ap©r and held in place by a couple of spadefulls of earth. If 

 the upjjer side of this cone were painted black the graft would, owing 

 to absorption of heat, be kept warm as well as dry. Such neans of 

 protection has not yet been prac'.ically tried; the idea occurred to the 

 writer during the compiling of these notes, and the suggestion is made 

 in the hope that it may prove of use to intending grafters during the 

 present spring, which, so far, does not promise very well for field 

 grafting. 



Thus executed and protected the graft may be left to itself for a 

 while. When growth starts the tie may requii-e cutting and the young 

 shoots will need tying up ; later on suckers and scion roots will need 

 attention and removal, operations which will be dealt with in a subse- 

 quent article. 



• Leu Yignen Americanett, leur greffagi et le'ir tail'e, by Felix Sahut, 1887, p. 370. This work was 

 awarded a gold medal by the French National Society ol' Agriculture. 



SOIL BACTERIA AND THEIR ENEMIES. 



Evidence is gradually accumulating iliat one great factor of soil 

 fertility lies in the relation which obtains between the numbers of 

 bacteria and of protozoa which live and move, aud have their being in 

 the soil. Broadly speaking, says the Gardeners' Chronicle, the 

 bacteria of the soil may be regarded as the gardeners' best friends, and 

 the protozoa — the antagonists and destroyers of the bacteria — as his 

 enemies. If for one reason or another the protozoa increase beyond 

 certain limits, the bacteria fall off in numbers, and the soil, the fertility 

 of which depends in a measure on bacterial activity, is no longer in a 

 condition to supply plant food — it falls sick. Hitherto, lie evidence in 

 support of this interesting and important hypothesis has been presump- 

 tive, rather than conclusive. It was largely of the nature of an inference 

 drawn from the effects of partial sterilization of the soil. As is now well 

 known, sick soil may be restored to health — that is, may be rendered 

 fertile once again — by exposure to a temperature of about 120 degrees 

 Fahr. At that temperature the active, " thin-skinned " soil pro'ozoa are 

 destroyed, but the "thick-skinned." more resistant of the soil bacteria 

 are not. Thus, when the soil cools down again, the bacteria find no 

 ojjposition to their increase. They multiplv rapidly, and in the course 

 of their growth and activity set free large quantities of material — and 

 particularly nitrogenous material — of a kind suitable for the nutrition 

 of plants. — The Leader, 12t.h May, 1917. 



