90 



THE AGRICULTURAL NEWS. 



March 21, 1908 



INSECT NOTES. 



Practical Remedies for Insect Pests. 



The article reprinted below, dealing with mea.sures 

 for the destruction ot insect pests affecting agricultural 

 crops, is from the pen of Mr. H. Maxwell-Lefroy, 

 formerly Entomologist on the staff of the Imperial 

 Department of Agriculture, and now holding a similar 

 position under the Government of India. 



Although some of the insects referred to by 

 Mr. Lefroy are not found in the West Indies, yet many 

 of the remedial measures recommended are of general 

 utility, and are reproduced as illustrative of lines of 

 treatment that may with advantage be adopted in 

 combating the ravages of insect posts in these 

 colonies : — 



The ultimate aim of the study of (U•^tructive insects 

 Is the discovery of some feasible mctlind. whereby their 



increase and destructiveness may 



eked 



crops 



preserved from their attacks. , In siu-li a quest, not only 

 must the habits and characteristics u( each individual pest be 

 considered, but it is of equal iniportancc to take into account 

 the conditions under which the croj) is grown, and the iacili- 

 ties there are for adopting anyniethod of repression. It is 

 [irobable tliaf the scicntitic methods that appeal^ to 

 the skilled fainier u{ iMirojieap countries will tie of little 

 value uheu applied to the cou(litions of Indian .\griculture, 

 and the best method that science reveals eau scarcely be 

 regarded as suilable to the present ijroblem. In very many 

 cases, the habits of a pest are sueli that ]iraetieally nothing 

 is possible unless we can utilize the most up-to-date 

 metiiods. In others, a weak |ioint can be found in 

 the life of the jiest when it can be successfully attacked I'V 

 .some very simiile means, (iiven some such simple remedy, 

 thorough co-operation in its a]iplicatioii over some area is 

 usually also necessary, and this is perhaps to he obtained only 

 when ail unnsnal abundance of a pest awakes the eultisator 

 t,, llie necessity of some aclioi. and, with a little pressure, 

 a fair trial can be gi\eii to the remedy. l';xperience has 

 shown that, for some pests, 1 lien; are such simple remedies 

 as can he applied by an indiviilual cultivator, and it is chiefly 

 these it is proposed to discuss'licre. 



One instance is the very sinqile method of checking tlie 

 stem borer of cotton, ulierelhe withered plants which contain 

 the pest can he removed and burnt with the pest within. 

 The cmei-ging beetle is not a wide-ranging insect, and is ajit 



10 confine its ravages to a small area ; the flestruction of the 

 withered plants in a cotton ^jlot does nuich to irrotcct that 

 particulai- ])lot, and though joint action over a large an^a 

 would be far more etVective, even a small [ilol may be largely 

 prolectt'd. 



The red Img of cotton is a pest that yields to the simplest 

 of all methods, destnu'tion by hand ; so also the very conunon 

 dusky bug, which often swarms in cotton bolls, can be checked 



by tiie simple preeauti f removing all the bolls that are 



worthless at the same time as the round ripe bolls are plucked. 



11 i. unfortunately a general practice to li'a\c <.ii tlie ],laiil 

 those bolls which have been so damaged by boll worm a,- to 



I. 



be not worth plucking ; the dusky hug finds there a secure 

 breeding place where it may lay its eggs, and where its young 

 can obtain food from the tuiinjured seeds ; from tlie.se 

 breeding places it spreads to other bolls and in them it sucks 

 the seeds, rendering, them useless for sowing or oil-extraction. 

 The removal of all .such bolls is a simple and efi'ective means 

 of in'eventiug the feeding of this pest. In cases where dusky 

 hug is very abundant, a further simple method is valuable ; 

 the bug collects in the bolls in great numbers and, when 

 disturbed, runs out and falls to the ground. The great 

 nuiiiber of ihese can be destroyed by tap]iing the boll while 

 a pot of water with a film of kerosene over is held below the 

 boll : practically all the bugs fall into the water and are 

 killed, and an iidested field can be very ra]ndly cleared. 



Among the inuior pests of cotton that are occa.sionally 

 very injurious is the leaf roller, a green cater] lillar that rolls 

 iqi the leaf into a funnel and lives inside. This pest commences 

 when the cotton (if sown with the first rain) is about a mr>nth 

 eld ; the rolled up leaf is very characteristic and an infested 

 plant has a peculiar appearance due to the unnatural position 

 of thesi' leaves. Every one of these leaves can be [jiidvcd ort' 

 with the caterpillar in, and if the -work is done early, the fir.st 

 brood can lie .so thoroughly checked that very little remains 

 to be done. If the first brood is missed, the increase is so 

 great that a vigorous crop will be completely .stripped later in 

 the season, and it then becomes a far harder task. Were 

 labour an expensive item, spraying with an arsenical poison 

 would be the .simple remedy, and both have been in use on 

 the I'li.sa K.xperimeutal Farm. As it is. we have here a ca.se 

 that particularly applies to our conditions, and one that is 

 within the reach of any cultivator. 



A jicst that is constantly rejiorted 

 districts is the moth borer. The principal 

 cut out and remove all the .shoots whicl: 

 canes and which have the in.sect in them, 

 ui-owing <listricts, especially in the Central Provinces and i'.om- 

 bay Presidency, this insect hiliernates in .sorghum plants, and the 

 caterpillar is constantly found in the stumps left in the ground 

 after the crop is cut. The removal of these stunii)s is a very 

 valuable remedy, since it removes the pe.st when it has no 

 other refuge and (lestroys the insects that would otherwise do 

 much harm later in the .season. Thi.s is a pi'actical mea.sure 

 well worth impressing on cultivators ; they know the insect, 

 tliev can be .shown it in the sorghum stump, and though they 

 do not understand its trausfm'inatieni, yet they are open to the 

 comnion-seiisc snggi'stion that these insects will increase 



irom cane-growing 

 remedy for ii is to 

 die in the young 

 In many sorghum- 



altack their 

 lliese reiiic' 

 if we could 

 of e\eiy pest, we would 1 

 with the pioblem. Apait 

 the methods ol ■ treatmeiil 



later on, and 



.Most .if 



methi ds. and 



crop. 



III 



are plain 

 1 such 

 le able to 

 from their 

 nieiitioni-d 

 be 



as demonstrations ; if a start can 



strafing such simple remedies, and tin 



be induced lo take them up at time: 



from the pest me fresh in his mind, the 



for further work in checking preventiblc lo.ss will ' 



common .sense 

 ioiiii> in I he life 

 leal mole etl'ectively 

 value as remedies, 

 are valuable al.so 

 made by demon- 

 agriculturist can 

 ' when the losses 

 foundation 

 ■ lai.l. It is 



astounding how universally the simplest remedies are 

 unthoughl of by the cultivator, ap))arently becaii.se the cpiestion 

 of checking pests never suggests itself until the overwhelming 

 numbers of a caterpillar av grasshoi)per make a pi-actical 

 remedy an iiiipn,, .ibility. In very many cases, if the jio.s.sibil- 

 ity of checking aininsect was known to the crop grower, he 

 would from his own intimate knowledge of his crops, be able 

 to picM'iit or idieek much of the loss that constantly <iccur.s. 



(7Vi //I' i-onliitiud.) 



