420 Journal of Agricultiue, Yictoria. [10 July, 1917. 



How TO Swab. 



From the theoretical considerations whicli precede, it is evident that 

 in order to be effectual, swabbing must be very tliorough; something 

 more is necessary than a mere sprinkling. The whole vine, and more 

 particularly all scars, must be wetted so thoroughly that all corners and 

 recesses in which sclerotia are often hidden will be penetrated by the 

 solution. It is evident that in this respect two applications (as already 

 advised) are better than one ; the second may reach scars missed by the 

 first. 



The newest wood (rods and spurs) no doubt requires closest atten- 

 tion, but the whole of the older wood, main-stem and all, must be wel) 

 wetted with the swab, so as to destroy any kystes and other resting 

 stages which may be harboring on or under the rough bark.* Some 

 years ago the removal of this rough bark was recommended. Such 

 work is costly, and does not. seem to be necessary. Pacottet considers a 

 thorough wetting with the acid solution as quite sufficient. Should 

 removal of the old bark be decided on, all fragments must be carefully 

 collected and burnt; to strip the bark and leave it on the ground near 

 the vine would be worse than useless. Likewise with pruuings; on 

 patches severely visited by the disease last year, these should be com- 

 pletely burnt, and care taken to see that no fragments are left lying 

 about. 



Swabbing is usually applied by means of a brush— an ordinary white- 

 wash brush will do. The solution being very corrosive, the brush cannot 

 be expected to last long. The only brushes which are at all suitable are 

 those which are free from n.etal parts and are bound with string instead 

 of wire. A small mop made of woollen rags, tied to a wooden handle, 

 may also be used. The method of application is of less consequence 

 than its thoroughness. A convenient appliance is mentioned by Brunet 

 in his recent work on vine pests. | 



M. Magen lias devised a special implement for tlie winter swab, wliich is 

 known by the name of '" Le Continu." It consists of a lead-lined receptacle of 

 2J gallons capacity, a rubber hose, and a brnsh. The liquid is conveyed by the 

 hose to the centre of the brush, which is lield by the workman. When the hose 

 is flowing, the brush is continually saturated with the solution. 



Somethin-g similar to this could, no doubt, be easily improvised, it 

 being too late to import these implements. A tap made of lead, be- 

 tween the hose and the brush, would no doubt prove useful for regulat- 

 ing the flow of liquid. 



Spray pumps are largely used in France, but they must be of 

 special design, since an ordinary spray pump would soon be destroyed 

 by the cori-osive liquid. Puir,ps designed for tlie purpose have recep- 

 tacles made of glass, or lined with lead, which metal is capable of resist- 

 ing sulphuric acid. The rubber hose can resist the solution fairly 

 well, but the nozzle must be made of lead or ebonite ; ordinary nozzles 

 would corrode very rapidly. 



The spray is said to be of cheaper and more rapid application than 

 the swab, though it is doubtful if it is as thorough; there must also 

 be a considerable loss of liquid with the former. 



* In South .\fric.i it is considered advisable to swal> trellisins posts. — See Af/ricuUurfU Journal of. 

 South Africa, July, 1906. " In the Vruchtbair flower garden a few vines grow on a high trellis supported 

 by wooden posts." The Wnes, but not the posts, were treated (witii acid iron sulphate) and the result 

 was that the disease was almost as bad as if nothing had been done wherever new shoots grew close to 

 the posts." 



t Raymond Brunet. Maladies et Insectes de la Vigne, p. 76. 



