27 



GENERAL APPLICABILITY OF FUMIGATION IN 



THE COLONY. 



Eighteen months ago, the writer stated in his annual report that 

 the gas treatment was too expensive for general adoption in the 

 Colony, although in some districts he believed it would pay well. 

 This statement was based upon an estimate of the cost of the outfit 

 and chemicals at the prices for which the different materials could be 

 purchased at retail in Cape Town. No draper would supply the cloth 

 at less than Is. a yard, and no chemist would sell the required grade 

 of cyanide at less than 4s. 6d. a pound. At these prices for the 

 materials, the statement that fumigation is too costly for general 

 adoption is entirely unwarranted, but it is not in the light of the 

 figures given in the preceding paragraphs. 



Kelative to the cyanide, the price has fallen over 25 per cent- 

 during the last fifteen months ; and the writer is now assured by a 

 Cape Town chemist that he will retail it at about Is. 9d. a pound. 

 At present little of it is sold, and this fact in part accounts for the 

 high price which was not lessened with the fall in the wholesale 

 price. Enormous quantities are imported into the Transvaal and 

 used in the extraction of gold. 



It is now safe to make the statement that, in general, fumigation 

 with hydrocyanic acid is the cheapest remedy for scale insects on 

 citrus trees in Cape Colony. It is not meant by this that the remedy 

 is entirely applicable when a few trees are concerned, as is generally 

 the case in town and suburban gardens. In the majority of such 

 instances the cheapest, best and true remedy is to uproot and burn 

 the trees. As long as they remain, they are a menace to the health 

 of numerous ornamental plants in their proximity. 



On isolated farms and in sections where the growing of citrus 

 fruits is not common, it will generally be cheapest and best for each 

 grower to fumigate his own trees. An outfit for use on a single 

 farm need not be expensive. If the trees are of about uniform 

 height, a single cover could be made to suffice for all. For the sake 

 of economy, the cloth should be purchased by the piece. A single 

 piece would answer for four Size I. tents, two Size II., or one Size III, 

 and one Size IV. A sheet about twelve yards across could be made 

 from three pieces of cloth, and enough would remain for a tent of Size 

 II. Considerable saving could be effected by having the sewing done 

 at home. Iron hoops from old casks might be made to serve the purpose 

 of the gas-pipe circle for a small tent ; and other means of reducing the 

 cost by home makeshifts will suggest themselves to the thrifty farmer. 



The trees might be covered and the gas generated before going in 

 to the evening meal, and thus one or more trees, according to the 

 number of covers, treated on every favourable night without necessi- 



