7 



With the scale insect, however, it is different. During the last five years this insect has become more and 

 more prevalent on cocoanut estates in Jamaica, and Mr. Morris appears to have corresponded with planters in 

 different parts of the Island, and kept the disease under observation during the whole time. The result of his 

 investigations, as detailed in the report above mentioned, are briefly as follows ; - The scale insect, in appear, 

 ance like a minute oyster or limpet, attaches itself to the under side of the fronds of the cocoanut palm, and 

 covers them with a thin silvery coating, which rubs off when scraped with a knife. Underneath the scale, one 

 of which is only about +he twelfth part of an inch in length, there lies an insect armed with a proboscis, by 

 means of which it penetrates into the tissue of the frond and sucks up its juices. Generally, when lifting up 

 one of the scales, there is found, not only the female scale-insect, but also a large number of eggs, which, 

 when hatched give rise to a colony of small scale insects. These ultimately escape by a small hole in the 

 scale, or general covering. It will be noticed that the cocoanut palm suffers from the scale insect by the loss 

 of its' juices, absorbed from the leaves by the myriad colonies of insects clustered beneath them. The disease 

 spreads by the colonies of scale insects being carried from tree to tree, or from estate to estate, by the wind. 

 It was first noticed in force in the Parish of St. Mary's, Jamaica. Like the aphis blight which appealed on 

 suova- canes some years ago, the scale insect has spread in the direction of the trade winds, and affected estates 

 to the south and west. The first appearance of the scale disease is shown by the outer frond turning brown 

 and withered, and ultimately becoming quite dead and dry. In this respect it differs from the beetle, where 

 the head is first affected and the outer leaves only at the last. If the scale disease is persistent it gradually 

 spreads from the outer to the inner IcaveB, but, so far as Mr. Morris' cbseivalions are concerned, the 6cale 

 disease does not destroy the trees, although it weakens them to such an extent as to spoil their bearing. To 

 planters the most important considerations, however, are, — (1) How has the disease arisen ? and (2) Mow may it 

 be checked or removed ? Quoting a very valuable little book, by Miss Ormerod called "A Manual of Injurious 

 Insects," lately reviewed in these columns Mr. Morris expresses his opinion that this disease has spread owing 

 to the unprecedented prevalence of dry weather, in the YVest Indies, and he finds that the severer the drought 

 the worse the disease. " Insects of this class multiply most quickly in dry weather, and on plants which are 

 sickly from drought, exhaustion by insect attack or other causes ; so that all measures of cultivation tending 

 to produce vigorous healthy growth are serviceable in counteracting attack ; and where circumstances allow 

 of the application of liquid manure, or of water to an extent to make the plant food in the soil invaluable, and 

 push on growth that otherwise was being checked by drought, such treatment would be desirable." 

 Several other points are touched upon, such as that cocoanut palms grown inland, where there is an absence 

 of salt in the soil, being less able to resist the disease, suffer more than those near the sea ; that where practi- 

 cable cocoanuts should have a good dressing of manure applied to their roots as soon as the disease appears, 

 and that irrigation be applied whenever practicahle. As regards other treatment, Mr. Morris mentions that 

 the fronds affected by the scale insects should be cut down and that they should be heaped up and gradually 

 burned under the trees to give off as much smoke as possible, without, however injuring the foliage by heat. 

 In fact, it is believed that by thoroughly smoking the insects in the first stages they may be destroyed, but be- 

 yond that it is hopeless to cope with a disease so widespread in its habit or so difficult to bring under careful 

 treatment. It is somewhat consolatory to learn that in Mr. Morris' opinion the disease is likely to be greatlv 

 reduced on the return of regular rains and that it cannot ultimately affect the value of cocoanut properties in 

 Jamaica. Planters in the meantime are, however, specially urged to take the simple steps noted above, and re- 

 duce the effects of the disease on their plantations as much as possible. 



Mr. Hart also noticed the disease in his Report for the year ending September, 1886, and men- 

 tioned various remedies. 



The following letter has already appeared in the Jamaica Gazette : — 



Botanical Department, Gordon Tow n P.O., 

 16th January, 1888. 



Sir, 



In continuation of my letter dated 7th September, 1837, No. 2424, on the Cocoanut disease in the neigh- 

 bourhood of Bath, I beg to report that on a recent visit to Port Antonio I found that the same disease was 

 attacking the Cocoanut Palms there, and especially the young plants. 



2. Mr. Watson, who has charge of Captain Baker's plantations, appears to have been successful in getting 

 rid of the disease on the young plants by a simple and inexpensive method. He placed a heap of dry leaves 

 &c, round the base of each stem and allowed it to burn for some time. The flames scorched and burnt the 

 outer leaves of the Palm, at the same time killing the scale-insects, and new leaves are putting forth, which 

 look healthy and free from the disease. I am inclined to think that the smoke caused by the burninf had a 

 greater effect than the heat, for it could penetrate to inner parts where the flames could not act. If so a 

 similar plan might be tried with even the tallest Palms, by packing the bases of the outer leaves with dry 

 bush, rotten wood, or some material which would give dense smoke without flame. Sulphur might also be 

 tried. The application of this or any other remedy should be tried at different times of the year, for a remedy 

 which would have no effect on the eggs migh completely extirpate the disease if applied when the your.'"- in- 

 sects are hatched out — probably about May or June. 



3. A Correspondent from the Grand Cayman informs me that the Cocoanut Palms have been infested 

 with apparently the same disease for forty years, and that " tens of thousands'' of trees have been destroyed. 



4. The subject is of great importance as a Cocoanut Palm in bearing is calculated to be worth Five 

 Pounds, and if the disease spreads much in Jamaica the total loss will be very considerable. 



5. It is to be hoped that the results of any experiments made for the extirpation of the disease will be 

 communicated to me, in order that they may be published for the benefit of others. 



I have, &c, 



W. Fawcett, 

 Director Public Gardens and Plantations. 



Note. — A subscription of 2/ will iasure the delivery at any Post Office in Jamaica of L2 numbers of the "Bulletin" 

 Application may be made at any of the Gardens, or by post to the Director of Public Gardens and Plantations Gordon 

 Town, P. O., Jamaica. 



