33 



also observeii on some trees that did not as yet show recognizable symp- 

 toms of the disease Whether such symptoms would ultimately develop 

 can only be determined by observations continued through a considerable 

 period. Mr, Wm. Cradwick of the Jamaica Agricultural Department has 

 undertaken to make farther field studies and as specimens of the scale and 

 cultures from the diseased tissues have been secured it is hoped we may 

 ultimately gain a better understanding of this interesting but obscure 

 trouble. 



If, as it seems probable, the scale is the first inciting cause of the disease 

 it should be possible to devise some remedial treatment. Owing to the 

 height of the trees and the method of growth, the scales being largely 

 sheltered by the fibrous sheathing bases of the leaves, the successfal ap. 

 plication of insecticides would be difficult but not necessarily impossible. 

 Mr. Cradwick will undertake some experiments on this line. 



An interesting experiment has been tried on one of the plantations of 

 the United Fruit Co., in firing the dead leaves and fibres hanging on the 

 diseased trees. The flame kills all the fruits and open flowers and most 

 of the expanded leaves but the apical bud is not injured and new leaves 

 and flowers are soon developed. This seems like heroic treatment, but two 

 trees were pointed out that had been fired six months ago when they were 

 in advanced stages of the disease ; now they seem entirely recovered and 

 are putting on a new crop of fruit This firing of the trees has also been 

 suggested as a remedy for the bud disease. The chances for success 

 would seem to be much less in that case for the disease so soon becomes 

 deeply seated. 



Coco-nut Trunk Borer : A few trees were observed where areas on the 

 trunk two or three feet or more in extent had been bored full of small 

 holes no larger than a knitting needle. Minute white larva were found 

 at the bottom of some of these burrows but noue were taken in onditioa 

 for identification. A rotting of the trunk soon follows these borings and 

 if the insect was abundant it would c luse considerable loss. It was only 

 observed in the grove and there only in a few trees. 



Coco-nutTrunk Rot : Afew cases were observed when some slight injury 

 allowed the entrance of a rot that destroyed the entire centre of the trunk. 

 In one case an outer rind of less than half an inch of healtl\y wood re- 

 mained, a rotten liquid running out when this was cut through. Strange- 

 ly enough the top of this tree still seemed healthy and vigorous, but the 

 rot in the centre of the trunk had reached to within a few inches of the 

 base of the bud. Such cases seem to be very rare but they shew the im- 

 portance of avoiding unnecessary wounds of the trunk. 



Banana Leaf Blight : On one locality at Stony Hill, north of Kingston 

 a serious banana disease was observed. It causes the browning of the vas- 

 . cular bundles in the veins and midrib ot the leaves. This is soon fol- 

 lowed by the blackening of the entire leaf blade and eventually by the 

 rotting of the leaf and petiole. It does not seem able to extend from the 

 petiole into the tissue of the stem. The terminal bud is not attacked 

 but continues t) push out fresh leaves. These soon become infected in 

 turn so that usually not more than three or four of the younger leaves 

 . are free from the disease. Infected plants are much stunted in growth 

 and do not bear fruit. In the small field where it was first observed fully 

 three-fourths of the plants were infected. The cent igion was in this case 

 probably introduced with the suckers that were used for planting as these 

 were said to have been taken trom some neglected patches in the 

 .neighbourhood, and a visit to these showed that they were also infected. 



