1 



...I 



would be a practical impossibility. That is to say, the expense oi 

 exterminating the Various scale insects which furnish conditions 

 favourable to the growth of the black bligh.1 would entail an enormous 

 expenditure of money, which would hardly be warranted until ii gave 

 evidence of being seriousl} injurious to a valuable crop, and it would 

 necessitate the destruction of so many trees and food plants of the 

 scale insects that the results might be more unfavourable and far- 

 reaching than would be supposed. The control, however, oi' black 

 blight and the scale insects it follows, is. on tic whole, a simple 

 matter on any given area. As an illustration of this point, I mighl 

 cite a few trees at Chelston and Strathmore, Barbados, which have 

 been sprayed during the past year : -- 



(a.) Lime trees at Chelston. These were badly attacked by 

 the Snow scale (Chionaspis citri), and the mussel scale 

 (Mytilaspis citricola) and the leaves were covered with 

 black blight. These were sprayed with Lefroy's mixture, 

 August 7, and again August 20. 1903. At this time (May 

 23, 1904) a few scales are to be seen, and on one branch 

 a few leaves are affected by black blight. 

 (b.) Breadfruit, sprayed with Lefroy's mixture August 20. 

 1903. For a long time after this spraying, this tree 

 appeared to be tree from black blight. For a few weeks 

 past a few leaves have been covered with black blight, 

 (c.) Barbados cherry (MalpigMa sp.) attacked by Protopul- 

 vinaria pyriformis. This tree was well covered on leaves 

 and branches by black blight. Sprayed with Lefroy's 

 mixture April 2. 1904. This spraying took off nearly all 

 the black blight, and killed the larger part of the scales. 

 A second spraying was given April 28. and now no black 

 blight is to be seen, and it is only by diligent search that, 

 living scales can be found. 

 (d.) Avocado pear, badly attacked by Frotopulvinaria pyri- 

 formis and black blight. Sprayed with Lefroy's mixture 

 twice in April, the second spraying occuring on the 28th. 

 The black blight is practically all off but a few live scales 

 are to be found at this time. < 'lie more spraying will 

 probably kill nearly all these, 

 (e.) Mango, badly attacked by the glassy star scale (Vinsonia 

 Stellifera) and black blight. Sprayed with same mixture 

 as the Pear. Scales practically all killed. ( less than 1 per- 

 cent, still alive) and black blight all off. 



15. These examples should serve to show that the black blight 

 can be controlled, and with very little cost and labour. 1 am of 

 opinion that if the Government would undertake a certain amount of 

 experimental work, so that estate owners could see the good effects 

 of spraying, and if they would then practise the methods that had 

 been found successful, the black blight would be controlled with 

 a minimum of trouble and expense. 



16. In conclusion. I would again point out that black blight is 

 unsightly but comparatively uninjurious ; the scale insects which it 

 follows may however become a serious pest, but they can be 

 controlled 



II. A. BALLOU." 



