84 



The disease evidently spreads slowly as it had not crossed a wid« hedge- 

 row separating this "infested field from one adjoining. It may never prove 

 troublesome, but the advisability of immediataly destroying all diseased 

 plants was strongly urged. If so destructive a disease should by any 

 chance become widely scattered the result would be truly disastrous. 



Apparently it is due to abacterial parasite. Cultures were obtained and 

 it is hoped to study the disease further. No evidence was secured as to 

 the means by which it is conveyed to the fresh leaves or from plant to 

 plant. So far as ktown it is confined to this one locality which is at an 

 elevation of seme 1,200 feet and on red land. Such locations are not con- 

 sidered to be adapted to bananas, yet all uninfested plants were growing, 

 and fiuiting satisfactorily. 



Orange Boot Grub: Orange growers, especially in the neighbourhood of 

 of Bog Walk, are much troubled by a grub that gnaws the bark of the 

 roots. Often the injury is sufficient to cause the death of the trees. 

 "Where the trees do not die, tlie growth ceases, the leaves turn yellow and 

 the crop fails. The grub is a footless larva probably that of Praepodes 

 vittata, one of the Curculionidae. (See Journal of Jamaica Agricultural 

 Society, January 18&8, p. 11.) From what 1 am told of the habits of this 

 insect it can best be destroyed when in the adult stage. The beetles are 

 said to gather in great numbers on the orange trees eating the foliage, if 

 such is the case, they could be destroyed by arseniacal sprays. They are 

 said to be clumsy flyeis, and to have the habit common to many of the 

 Curculionidae of falling to the ground when jarred or disturbed. This 

 should make it possible to catch them by jarring on to sheets as is done 

 with the peach curculio. The larvae could doubtless be killed in the 

 ground by injections of carbon di-sulphide, but whether this could be done 

 without injury to the tree and at an expense that would make it practi- 

 cable, can only be detei mined by carefully conducted experiments in the 

 field. Whether tobacco or other substances worked into the soil about the 

 tree would prevent the depositing of eggs, is [ erhaps worth trying. The 

 insect is thought to be a general feeder, and is not confined to the orange, 

 though it seems to be particularly partial to all citrus fruits. Some grow- 

 ers claim that they have suffered more when practising clean cultivation 

 than when weeds and bush are allowed to grow for part of the year the 

 roots of which may serve to divide the attention of the grub. 



In this connection it may be noted that orange scale insects are not like- 

 ly to prove seriously troublesome for in the moisture regions at least they 

 are quickly destroyed by fungus parasites. 



The orange rust mite occurs on the Island but it only seems troublesome 

 on certain wet heavy soils. 



Cocoa Stem Conker : This trouble was only observed in the neighbour"" 

 hood of Port Maria, but it probably occurs in other parts of the Island- 

 Slightly swollen areas occur on the trunk or larger branches. 'I he tissues 

 in the central part of the swellings soon die and the yellow perithecia of 

 some Nectiinaceous fun<;us develop on the baik. The swelling continues 

 to grow at ihe margin lill finally it often girdles and kills the tree. Keep- 

 ing the trunks and larger branches painted or sprayed with Bcirdeaux mix- 

 ture should be a complete protection from this disease. It would alsc des- 

 troy moss and lichens and keep the trunks in a clean, healthy condition. 

 Promptly cutting out ef the diseased areas and painting the cut surfaces 

 with sulphate of copper or sulphate of iron solution and then coating with- 

 tar or paint would piobnbly in most cases save trees that are already at- 

 tacked. 



