5 



Area. 



Weight of Manure (in cwts.) necessary for experimental plots of 



ONE acre in area. 



P.K.N. 



A. a 



Basic Slag. 



Sulphate of 

 Ammonia. 



Sulphate of 

 Potash. 



Nitrate of Po - 

 tash. 



^4 

 2 



Chloride of 

 Potassium. 



(1) 1 acre 



(2) " 



(3) " 



(4) " 



(5) " 



(6) » 



(7) " 



(8) " 



(9) " 

 (10) " 



3 



3 



5 

 5 

 5 

 5 



i'i 



"2 



"2 



24 



"2 



"2 



3 



2 



"2 



3 



SUGAR CANE DISEASE. 



The following copy of a letter from the Director of Kew Gardens has been transmitted by the 

 Secretary of State for the Colonies. 



Mr. Massee's report will be published later. 



Royal Gardens, Kew, to Colonial Office. 



April 6th, 1893. 



Sir, 



I have the honour to inform you that for some time past numerous communications have been ad- 

 dressed to this Eatablishment respecting a disease which has made its appearance in the West Indies 

 amongst the Sugar Canes. 



The injuries which the canes suffer from the attacks of insects, popularly known as "borers" 

 have long been known, and have been now pretty completely studied. A tolerably exhaustive account, 

 embodying everything that is at present ascertained, by Mr. Blandford, will be found in the number 

 of the Kew Bulletin for July and August of last year. 



The disease which is now complained of is of a more insidious kind, and is due to the attacks of a 

 minute fungus. Considerable discussion has arisen as to whether the mischief is produced by one 

 fungus or by several, and further as to whether the attacks of the fungus precede, follow, or are con- 

 comitants of the injury inflicted by the borers. 



Such material for investigation as has been hitherto sent to Kew from the several Botanical Estab- 

 lishments in the West Indies has been inadequate, and has only yielded ambiguous results. I, how- 

 ever, received a letter early this year from Mr. John R. Bovell, Superintendent of the Botanical Station 

 at Dodd's Reformatory, Barbados, from which I enclose an extract advising me of the dispatch of a 

 very complete series of diseased canes 



I entrusted these to Mr. George Massee a well-known expert in Mycology, who made a careful 

 study of them in the Jodrell Laboratoi'y at Kew. I enclose a copy of the preliminary report with 

 which he has furnished me. This completely establishes that : — 



The disease is due to a fungus, a species of Trichosphceria which, like many allied minute fungi, has 

 the peculiarity of possessing more than one reproductive phase. These different phases have been 

 mistaken for distinct fungi, but as a matter of fact they are not so, but are capable of reproducing one 

 another. 



The Trichosphceria is evidently a very destructive parasite. It can effect a lodgment on the 

 young leaves of the Sugar cane, but not on the mature ones. But it readily takes advantage of any 

 wound such as is produced by the removal of young shoots or by the different kinds of '* borers." It 

 is this latter circumstance which has led the malady which the fungus produces to be regarded as 

 having some connection with the " borers." 



No practical remedy can be suggested to check the progress of the disease beyond the careful 

 destruction by burning of every diseased cane. 



I may be permitted to suggest that a copy of this letter should be communicated to the Govern- 

 ment of Barbados and to such other of the West Indian Colonies, interested in sugar production, as 

 the Secretary of State may deem desirable. 



I may add that Mr. Massee proposes to published a detailed account of the Trichosphceria which 

 possesses many points of scientific interest, in the "Annals of Botany." 



I am, &c., 



W. T. Thiselton Dyer. 



