282 



THE AGRICULTURAL NEWS. 



August 28, 1915. 



INSECT NOTES. 



NOTES ON PORTO RICO INSECTS. 



, ONTROL "I Till CHANGE OB MOLE ' RH Kl r. 



The Ohanga or mole cricket (Scapteritcus didactylus) 

 has been a serious pes) in Porto Rico for several yea 

 and this, or other related forms, has been troublesome in 

 other West Indian localities. The Porto Rico B ird of 

 Commissioners ol Agriculture has recently issued Circular 

 \ G, entitled Control of the Changa, by Messrs. S. S. 

 Grossman and G. N. Wolcott. 



The method ol control which has been found satisfactory 



consists in the use of a poi s bait prepared by mixing 



[001b of low grade flour and S\ to 3 ft. of Paris green 

 This is applied in a ring about thl planl to be protected or 

 sown broadcast over the surface bf the ground. 



The experiments which have Jed to tin on of this 



poison bait were c lucted principally in connexion with the 



tobacco crop and they have extended over several years 

 The same treatment has been found applicable to sugar-cane 

 and vi rops. 



The ring method is particularly applicable to tobacco 

 and sugai cane, kbout a heaping teaspoonful of the mixture 

 is used per plant and it is applied' in a shallow trench about 

 1 inch deep and about 3 inches, from the plant, that is to 

 >av. the ring -will be about 6 inches in diameter with the 

 plant in the centre. The poison mixture should not be 

 allowed to come nearer than '■'< inches to the plant nor 

 should any of it be dropped on the plant, as it lias a burning 

 effect mi the roots and leaves of plants. 



In using this bail in the broadcast method, it is neces 

 sarytofree the soil of plant growth as far as possible by 

 ploughing, forking or hoeing in order to deprive the mole 



crickets .it i I. In about a week the application is made, 



amounting to aboul ■'■ ll(| ft>. of the mixture. After anothei 

 four or five days, during which the changas have had an 

 opportunity to eat the poison mixture, planting may take 

 place in the ordinary way. 



In an experiment with this method of application in 

 a vegetable gardeaven i tory results were obtained. 



The experiment consisted of twenty lots of 300 plants 

 each; ten lots (3,000 plants) were planted on the land which 

 p.,,! received applications ol the Paris green and flour 

 ml. equal number was planted on land which 

 had n"t been poii id 



In the latter case 3,000 plants were pi inted on land which 

 Pad not received an application of poison, 1,405 grew and 



1,595 were lost, while in thai porti There the poison was 



applied only fifty six plants wen- lost and 2,944 plants grew. 



Oh the treated land less than 2 pel cent, were lost while 



on the other, the I"— was 53 pi f cent. 



Thecostoi this treatment is rather high, amounting to 



lor $10 per acre, including labour, when the flour costs 



. per ton (2,000 IK) and Paris green is obtainable foi 



Ei ! ■ per ft). En the opinion ol the writers of 



the Ci culai the expeusi of this treatment is fully justified 



since the mole crickets are all killed out and an almost 

 perfect stand of plantais ob linst an imperfect 

 stand in spite ..I repeal and supplying and 

 eventually a short crop resulting from an irregular and 

 pitchy stand, in land where the chat [8 ll d and where 



no treatment is given or where measures other than that 

 mentioned above are tried. 



INSECTS UTK'I'INi. VEGETABLE CROPS in PORTO RICO. 



Bulletin Xo. 192 of the United States Department ol 



Agriculture, by Thos. II. Joi a brief account of the 



principal insect pests crops in Porto 



Rico. Many of tl nown in the 

 Windward and Leeward Islands 



[n the case of thatinsects which occur also in the i 

 islands, those in Portq B inlj ■ t general interest, but in 



thecase of asi pes) which does not occur in these islands 



and which is liable to l i which might be introduced from 



Porto Rico a very considerable amount of importance should 



1 e attached to it. 



It will be remembered that in a recent number ol the 

 Agricultural News (see issue for April 24, 1915) an account 

 was given of the sweet potato weevil | ( 'plas loi m icai ivs . This 



insect was there recorded as occurring in India and the Ear 



East, in Africa, the United States, Jamaica, Cuba, British 

 Guiana, and the Bahamas. It is now recorded from Porto Rico, 



and as this insect docs not occur at present in the Leeward 

 and Windward Islands and Barbados, great care should be 

 rcised to prevent its introduction. Cylas foi 



is fully as serious a pest as the Si ' ■has 



batatae), and if it became establi hi nj of these islands 



it would very considerably redui pot itoes. 



The Southern beet webworm (Pachyz'iwchla bipv 

 talis), the larva of a small moth, has been found attack- 

 ing garden beans and thi i nrd bean (Canavalia 

 furmis) in addition to weeds oi the genus Amaranthus. On 

 the garden bean and the Amaranthus, the leaves were - 

 and these wen' webbed togethei forming shelter for the 

 . but in the case of the sword bean the larvae were found 



inside the green pods. 



This is of interest in o w ion with the appei i 

 pests "I beans in other West Indian island 



The Mole cricket (Scapterin I is regarded as 



the most serious pest of' vegetable crops < >t these the : 

 egg plant, turnip and cabbagi are stated to be most affected, 

 whilst the watermelon, bean, swe I potato, and yam 

 seldom or never attacked. 'The method control'for this 

 insect given above will probabb tacks of this 



pest to be hciter controlled in the m in the p 



II. A. B 



Fumigation ot Baled Cotton. -Iu com 

 with the article on the Pink Boll v pp ired in the 



last number of the Ag* si uli\ rai Vt I ivi ing efen 



•ii that insect and the •' of the I li I Horticultural 



Board to fumigate haled cotton shou rest: 'W. I >. 



Hunter and G. B. Sudworth, ol th< Federal Horticultural 

 Hoard, had a confen ace at Pi Pa., on April 1 I. with 



i he designers of a to ich b ch m b dapted for the 



fumigation of bales of cotton. On April 20 a conference 

 washeld with the Department rding proposed action 



of the Federal Horticultural M I, regarding the fumig 



of all foreign cot ton rea to destroy the 



immature stages of '•■ Ltepresental 



cotton nulls from all parts of tl were present.' 



\ i . -. S . •">. June 1915.) 



