250 



THE AGRICULTURAL NEWS. 



August 11, 1906. 



INSECT NOTES. 



prevalent 



i (Vol IV, 



nutmegs. 



Black Blight on Cacao in Grenada. 



Readers of tlie Ajji-tii'ltcmil Xincs nie probably 

 well aware of the refationsliip existing between the 

 fungoid growth known as ' black blight ' and scale 

 insects — that the former finds suitable conditions for 

 growth in the excretions of the scale insects. 



Black blight has for some time been very 

 in Grenada, but, as stated in the Agricultural A'euw 

 p. 394) ' scale insects rarely attack cacao and 

 although cases are known in Grenada of such attacks, and 

 wild and uncultivated plants :;re frecjuently attacked and 

 furnish a source from which the infestation may spread 

 to cultivated plants of certain kinds.' 



Such an attack has recently occurred on an estate in 

 Grenada, where the scales and black blight have spread to 

 the cacao from neighbouring bread-fruit and mango trees. 

 The scale insects were found, with the black blight, on the 

 cacao leaves just as on the ordinary trees, which can be seen 

 all over the island. 



On the advice of the Agricultural Instructor, the infested 

 trees have been promptly dealt with. They have been 

 entirely stripped of leaves, lime wa.shed, and sprayed. It is 

 very desirable that cacao planters should keep a careful watch 

 on their trees for similar attacks, which must be dealt with 

 promptly. 



Cotton attacked by the Root Borer of the 

 Sugar-cane. 



In some of the fields of young cotton in Barbados 

 there is evidence that the root borer of the sugar-cane 

 has now added the cotton ])lant to the list of those 

 which are subject to its attack. Here and there in the 

 fields the leaves of the. young plants have been seen 

 wilting, and on being talsen up, such plants have always 

 been found with their roots damaged by a grub. 



At first the damage .was attributed to the cut worm, but 

 it was found that the ropts were being cut some way below 

 the ground, not at the si,irface as is the case with the cut 

 worm. I 



seen from the side, magnified about twice. A full description 

 of this pest will 3>e found in the West Indian Bullttin 

 (Vol. IV, pp. 37-47). 



As all the damage done by these grubs is below the 

 surface of the ground, is is somewhat difficult to deal with 

 the pest. 



Poisoned bait has been applied in infested fields, buried 

 2 or 3 inches below the surface and near the roots. The 

 grubs appear to have been destroyed. 



Another way of dealing with the pest is to dig up the 

 grubs. This was done on one estate where there was a bad 

 attack. No ditticulty was experienced in finding the grubs 

 when the soil was turned up from around the roots of plants 

 just commencing to wilt, though it is impossible to find 

 them when the plants are dead. 



The poisoned bait is the same as that used to destroy 

 the cut worms, and is made by mixing 1 lb. of Paris green 

 and 30 It), of pollard with molasses and water. 



So far, the pest has not given any serious trouble, and 

 no ditticulty has been e.xperienced in getting a good stand of 

 young cotton in the fields in which it appeared. It will be 

 well, however, for planters to be on their guard against the 

 root borer. 



Fig. 15. Grub of thij) J!oot Boker ok the Su<;ap.-c.^xe. 



In this case the pest has been recognized by the 

 Rev. N. R. AVatson as' the root borer of the sugar-cane 

 (Diajwepes: abbreviatus). Fig. 15 .shows the grub, where it is 



HURRICANE INSURANCE IN THE WEST 

 INDIES. 



Tropicid Life, for June, has the following: — 



The Financial and Commercial Suj)plement to The 

 Times of June 11 opened with an article, some two columns 

 in length, on the West Indian scheme for insuring against 

 hurricanes and storms. 



Arrangements have been made to enable the scope of the- 

 scheme to e.xtend to most of the British and French Islands 

 which are subject to cyclonic storms. . . . 



The most dangerous months are considered to be August 

 and September. During this period the cane fields are 

 not liable to such serious damage as later in the year, though 

 in the French Islands, where the canes are planted 

 earlier, they sufter more. For buildings on the sugar 

 estates, a premium of 1 per cent, is suggested by Jlessrs. 

 Henry Head i^- Co., Limited, who have worked out the 

 scheme. This, however, is considered somewhat high. 



With cacao and limes, it is proposed to value them, in 

 case of damage, at 5s. a tree. On estates, as in Jamaica, 

 where bananas are planted between the cacao, the.se, when 

 damaged, will have to be paid for at a rate to be agreed on 

 later. With cocoa-nuts no fixed premium or scale of 

 compensation has been fixed upon as yet, but there should be 

 no difficulty in arriving at a satisfactory understanding on 

 these points. Coffee is on a somewhat different footing. 

 Owing to the great difference between the yield of the trees, 

 the difficulty of assessing the damage would be very great. 

 With cotton it would be impossible to insure the crop for 

 twelve months, like other products. On the suggestion of 

 Dr. Francis Watts, it is proposed to insure cotton during the 

 hurricane month.s alone, and, in the event of the plants being 

 damaged bj- a hurricane, to pay the planter a fixed sum per 

 acre, by way of compensation. Orange growers, it is thought, 

 are not likely to insure, though possibly some of Tropical 

 Life's friends will disagree with this statement. Arrowroot 

 is not subject to serious damage, whilst rubber in the West 

 Indies has not yet been grown extensively enough to trouble 

 about, though, no doubt, later on it could be assessed at per 

 tree, the same as cacao. 



