378 



THE AG1ULTLTURAL NEWS. 



November 20, 1915. 



INSECT NOTES. 



THE CONTROL OF ANTS WHICH TAKE 

 AWAY ONION SEED. 



St. Vi grow ire faced « itfa the difficulty 



thai so -""ii ;is seed is planted, it is carried away by ants. 

 [• u onion industry is to be established in the Colony, the 

 control of ants must be undertaken, as they may remove the 



- 1 before it germinates, and may even 



■ i\ those seeds which have germinated, bj biting holes 

 in the young -hoots. 



An account has been received "f various experiments 



performed at the Experiment Station in St. Vincent in 



aexion with the control ol these pests. Certain of the 



experiments have given only negative results; nevertheless, 



the experiments are instructive and may be described. 



Two species of ant seem t<> be concerned in the trouble. 



One of these is the ordinary black 'stinging ant' which is so 



-tanth presecl mi cotton plants where it feeds on the 



sweet juici exuded by the cotton aphis. The other kind is 



.similar in general appearance, but the legs are rather longer. 



Aftei tli I ieds have been prepared and before 



planting, it is recommended that they be 'burnt off. This 



be d me I J spreading a layer of dry grass, bush or trash 

 over the beds and setting tire to it. A large number of ants 

 and other insects as well as weed seeds will be destroyed 

 by this procedure, and the germination of the seed when 

 sown will be facilitated. 



After burning it is advisable to place a few onion - 

 on pieces of paper in various parts of the seed bed, and keep 

 these under observation. If ants are still presenl they will 

 be seen to take away the seed, and the control of them must 

 be undertaken. 



The following experiments have been tried:— 



(a) J'oisoniny the ants with acetylene ;/as. — The 

 entrances to the aests were located by tracking the ants. 

 A piece ol calcium carbide was pushed 1- tar as possible 

 into the hole, and water poured down. The hole was then 

 m lint. It was thought thai the acetylene 

 so generated would penetrate to all parts of the nest and 

 poison the ants. The results did not justify expectations. 

 A large number of ant- were undoubtedly killed, but it seems 

 that the habit <i the- insects is to live in comparatively 

 small colonics with many outlets. This method oi control 

 was therefore judged to be impracticable and uncertain. 



(/,) Treating tht i-bed with I •• Vaporite 



sprinkled over the seed-1 deterrent effect upon 



1 he etl'e ;t -""ii wore off. 

 J'rea ■ ith " pasti mat itene and 



wood-ashes. — This was unsuccessful. The ants carried awa\ 



the Seed. 



(d) Treating th» seed with *< 1-SoO solution of con 



'I'lii- experiment was also unsuccessful. 



Attn baiti an I ! . tiling tht m 



with h'lt wai - less has been met with along this line 



oi work, and onion growers are strongly recommended t«. 



follow out tiie method I 1 ibed below. \m. 1 



some preliminary trials it was discovered thai pieces of ripe 



pear, and -mall pieces of meat, or of bone with 



a little 11, icl d, constituted the besl bait, the ants 



being attracted to them in very large numbers. A number 



ot pice, "i avocado pear were placed on the I it a 



distance apart oi aboul 18 inches, A- rum 



l.ei oi ants wen- attracted, the bail and tic- soil immediately 



underearth, ired with ants, w vessel ot 



hot water. This was repeated, the work going on continuously 



for a few hours, ffexl da] the ants refused t" take any pear, 

 ■11 seed si al ered in various puts of the seed-lied was 

 ijuite unmolested. Pieces ol meal were pul down, and as fast 

 as the ants gathered on these they were destroyed. A large 

 reduction in the number of ant- in the vicinity of the -eel bed 

 was thus effected, and the seed germinated without giving 

 much trouble. 



It may be pointed out that these ants are likely to be 



abundant (a) in newly cleared land, (b) in land which 



iii- previously been in corn, cotton or canes. The ants 



make their nests in fields devoted to these crops in order to 



feed upon the sweet juice exuded by the cotton aphis, and by 

 the sugar cane mealy-bug. 



In view of the clipping experiments which are soon to 

 take place in Antigua, attention may be called to Bulletin 

 No. 259 of the I'nited States Department of Agriculture, 

 which deals with studies on ovulation changes in arsenical 

 dipping baths. It appears that arsenites are readily changed 

 into arsenates by the action of bacteria, if the liquid is left 

 exposed and undisturbed too long. This should be avoided 

 asmuchas possible, becau e irsenate is not such a powerful 

 tickicide as arsenite. The use of formalin as a preservative is 

 -- 'ed. but in the ordinary way it doe.- ii"t seem that 

 it- employment is worth while from a business point of view. 



INDIAN POPULATION IN CROWN COLO- 

 NIES AND PROTE0TORATES. 

 The following return, compiled from the 1911 

 1 1 -11- reports, 1- taken from the Wealth of India for 

 July DM.,. It is ofinteresl in connexion with West 

 Indian Immigration ami the recent report on the same 

 by the Governmenl of India. Adults have been 

 regarded as persons aged sixteen years and upwards, 

 The high proportion of males to females will be noticed 

 as a typical feature of the figures given. It is a feature 

 which is not wit hmit considerable social and economic 

 significance: — 



British Guiana:,— Total Population 309,041, Indian, 

 lL'b.:.17. Adult (Males 53,083, female- 34,779,) -, - 

 Ceylon, Total Population, 1,110,367., Indian, 170,651; East 

 Protectorate, Total Population, 1,000,000, Indian 

 11,886; Fiji Islands, Total Population, 139,541, Indian 

 50.2S6, Adults (Males 29,062, Female, 8,785.) 28,847; 

 Jamaica, Total Population, 831,383, Indian Population, 



I 7, "SO. Adults l Male. 7,127, Female- 1,775,) 1 1,912. 



Windward Islands: -Grenada, Total Population, •'><;. T"^ 

 Indian, lob; St. Lucia, Total Population, 19,877, Indian, 

 2,064; St. Vincent, 1 1,877, Indian, 376. 



Leeward Island-; Antigua (with Barbuda and Redonda) 



1 Population, 32,296, Indian. .".; Dominica. Total 



tiou, 33,863, Indian. 8; Montserrat, Total Population, 

 12,196, Indian, 2; St. Christopher and Nevis, Total 

 Population, 13,403, Indian, 38; Virgin Islands, Total Popu 

 lation, 5,562; Malay state- i Federated). Total Population, 

 1,036,999, Indian,' 1 7 U . I *;-. Adult- (Males 116,626, 

 Female- 28,368) 144,994; Mauritius, Total Population 

 "77. ii-:!. Indian (a) 257,697, Adults (Male, S'f.'J'.Hi, 

 Females 71,833) 161,829; Seychelles, Total Population, 

 22,691, Indian. 120; Straits Settlements, Total Population, 

 714,069, Indian. 82,055; Trinidad and Tobago, Total 

 Population, 333,552, Indian, 50,585, Adults (Male- 31,989, 

 Female- 17,159) 19,148; Uganda, Total Population, 



2,843,325, Indian, 1,622. 



